Atrial Fibrillation (Clinical)

Epidemiology and Etiology

Epidemiology^[6,12,21]

• Most common form of cardiac arrhythmia
• Incidence Incidence The number of new cases of a given disease during a given period in a specified population. It also is used for the rate at which new events occur in a defined population. It is differentiated from prevalence, which refers to all cases in the population at a given time. Measures of Disease Frequency increases with age
• 70% of patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with atrial fibrillation Atrial fibrillation Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation ( AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation) are > 65 years old
• More common in men (but if affected, women are more likely to be symptomatic and develop complications)
• More common in Caucasians than African Americans, Hispanics, and Asians

General risk factors for cardiovascular disease^[2–4]

• Advanced age
• Hypertension Hypertension Hypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter. Hypertension
• Diabetes Diabetes Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance. Diabetes Mellitus mellitus
• Smoking Smoking Willful or deliberate act of inhaling and exhaling smoke from burning substances or agents held by hand. Interstitial Lung Diseases
• Obesity Obesity Obesity is a condition associated with excess body weight, specifically with the deposition of excessive adipose tissue. Obesity is considered a global epidemic. Major influences come from the western diet and sedentary lifestyles, but the exact mechanisms likely include a mixture of genetic and environmental factors. Obesity
• Sleep apnea Sleep apnea Repeated cessation of breathing for > 10 seconds during sleep and results in sleep interruption, fatigue, and daytime sleepiness. Obstructive Sleep Apnea

Risk factors for AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation^[1–3,7]

• Usually associated with some underlying heart disease
• Most common chronic disease associations are hypertensive heart disease and coronary heart disease Coronary heart disease Coronary heart disease (CHD), or ischemic heart disease, describes a situation in which an inadequate supply of blood to the myocardium exists due to a stenosis of the coronary arteries, typically from atherosclerosis. Coronary Heart Disease
• 15%–30% of cases are idiopathic Idiopathic Dermatomyositis or not associated with any known risk factor

Mnenomics

Pathophysiology and Classification

Pathophysiology^[1–3]

• AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation is caused by re-entrant electric conduction Re-entrant electric conduction Atrial Fibrillation.
• Re-entrant pathways can be due to:
  • Fibrosed tissue
  • Atrial dilation (e.g., congenital defect, post-MI, valvular disease, hypertensive heart disease)
  • Abnormal accessory pathways (e.g., WPW syndrome)
• Most common site of the rapid atrial firing that triggers AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation is the pulmonary veins Pulmonary veins The veins that return the oxygenated blood from the lungs to the left atrium of the heart. Lungs: Anatomy.

• Heart rate Heart rate The number of times the heart ventricles contract per unit of time, usually per minute. Cardiac Physiology: 
  • Atrial rate > 300/min
  • Some beats are irregularly modulated by the atrioventricular (AV) node
  • Ventricular rate = 90–170/min
• Effects: 
  • Atrial remodeling: irregular impulses and contractions lead to progressive dilation and fibrosis Fibrosis Any pathological condition where fibrous connective tissue invades any organ, usually as a consequence of inflammation or other injury. Bronchiolitis Obliterans of the atria → higher risk for AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation → vicious cycle of pathology 
  • Asynchronous contractility → atria lose systolic function 
  • Rapid uncontrolled atrial contractions ( > 300/min) → slower pass through the AV node → uncoordinated ventricular contractions (90–170/min) → tachycardia Tachycardia Abnormally rapid heartbeat, usually with a heart rate above 100 beats per minute for adults. Tachycardia accompanied by disturbance in the cardiac depolarization (cardiac arrhythmia) is called tachyarrhythmia. Sepsis in Children
  • Decreased cardiac output Cardiac output The volume of blood passing through the heart per unit of time. It is usually expressed as liters (volume) per minute so as not to be confused with stroke volume (volume per beat). Cardiac Mechanics → stasis of blood →  promotes thromboembolism Thromboembolism Obstruction of a blood vessel (embolism) by a blood clot (thrombus) in the blood stream. Systemic Lupus Erythematosus 
  • Decreased cardiac output Cardiac output The volume of blood passing through the heart per unit of time. It is usually expressed as liters (volume) per minute so as not to be confused with stroke volume (volume per beat). Cardiac Mechanics → heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR)

Classification^[1–4,21]

• Paroxysmal: AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation that starts spontaneously and terminates spontaneously or with intervention within 7 days of onset; episodes may occur with variable Variable Variables represent information about something that can change. The design of the measurement scales, or of the methods for obtaining information, will determine the data gathered and the characteristics of that data. As a result, a variable can be qualitative or quantitative, and may be further classified into subgroups. Types of Variables frequency
• Persistent: AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation that fails to self-terminate within 7 days, requires pharmacologic or electrical cardioversion Cardioversion Atrial Fibrillation to terminate
• Long-standing persistent: AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation that has lasted for more than 12 months
• Permanent: AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation that is unresponsive to treatment, patient and doctor decide to no longer pursue a rhythm control strategy
• Other descriptive terms:
  • Lone:^[2,4,6]
    • Use of term is controversial and discouraged
    • Previously defined as paroxysmal, persistent, or permanent AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation with no structural heart disease, typically in persons < 60 years old, the lowest risk of complications → patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship have a CHA₂DS₂-VASc score of 0
  • Secondary:^[7]
    • Treatment focuses on the underlying condition to resolve AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation
    • AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation recurs even in those with precipitants, indicating that risk of thromboembolism Thromboembolism Obstruction of a blood vessel (embolism) by a blood clot (thrombus) in the blood stream. Systemic Lupus Erythematosus and arrhythmia remains present.
  • Subclinical:^[4]
    • AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation in asymptomatic individuals without a prior diagnosis of AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation; often found in the context of implantable cardiac monitoring devices
    • Natural history in affected individuals is often progression to clinical AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation.
    • Often seen in heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR)

Clinical Presentation

• AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation is often asymptomatic.^[1,14,21]
• If patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship experience symptoms, these are often nonspecific and variable Variable Variables represent information about something that can change. The design of the measurement scales, or of the methods for obtaining information, will determine the data gathered and the characteristics of that data. As a result, a variable can be qualitative or quantitative, and may be further classified into subgroups. Types of Variables.
  • Palpitations Palpitations Ebstein’s Anomaly
  • Tachycardia Tachycardia Abnormally rapid heartbeat, usually with a heart rate above 100 beats per minute for adults. Tachycardia accompanied by disturbance in the cardiac depolarization (cardiac arrhythmia) is called tachyarrhythmia. Sepsis in Children
  • Chest pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways
  • Fatigue Fatigue The state of weariness following a period of exertion, mental or physical, characterized by a decreased capacity for work and reduced efficiency to respond to stimuli. Fibromyalgia
  • Dyspnea Dyspnea Dyspnea is the subjective sensation of breathing discomfort. Dyspnea is a normal manifestation of heavy physical or psychological exertion, but also may be caused by underlying conditions (both pulmonary and extrapulmonary). Dyspnea
  • Syncope Syncope Syncope is a short-term loss of consciousness and loss of postural stability followed by spontaneous return of consciousness to the previous neurologic baseline without the need for resuscitation. The condition is caused by transient interruption of cerebral blood flow that may be benign or related to a underlying life-threatening condition. Syncope
  • Confusion
  • Mild dyspnea Dyspnea Dyspnea is the subjective sensation of breathing discomfort. Dyspnea is a normal manifestation of heavy physical or psychological exertion, but also may be caused by underlying conditions (both pulmonary and extrapulmonary). Dyspnea
  • Embolic event
• If symptoms are atypical → notice signs of the underlying disorder (e.g., exophthalmos in hyperthyroidism Hyperthyroidism Hypersecretion of thyroid hormones from the thyroid gland. Elevated levels of thyroid hormones increase basal metabolic rate. Thyrotoxicosis and Hyperthyroidism, murmur in the case of a valvular defect)
• Complications of long-standing AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation:
  • Signs of heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR) ( pulmonary edema Pulmonary edema Pulmonary edema is a condition caused by excess fluid within the lung parenchyma and alveoli as a consequence of a disease process. Based on etiology, pulmonary edema is classified as cardiogenic or noncardiogenic. Patients may present with progressive dyspnea, orthopnea, cough, or respiratory failure. Pulmonary Edema, orthopnea Orthopnea Pulmonary Edema, paroxysmal nocturnal dyspnea Paroxysmal nocturnal dyspnea A disorder characterized by sudden attacks of respiratory distress in at rest patients with heart failure and pulmonary edema. It usually occurs at night after several hours of sleep in a reclining position. Patients awaken with a feeling of suffocation, coughing, a cold sweat, and tachycardia. When there is significant wheezing, it is called cardiac asthma. Pulmonary Edema, dyspnea Dyspnea Dyspnea is the subjective sensation of breathing discomfort. Dyspnea is a normal manifestation of heavy physical or psychological exertion, but also may be caused by underlying conditions (both pulmonary and extrapulmonary). Dyspnea at rest, pitting edema Pitting edema Edema caused by excess fluid without excess colloid. Leaves “pits” due to fluid displacement when pressure is applied to the area Edema, S3 S3 Heart Sounds, S4 S4 Heart Sounds)
  • Signs of embolization Embolization A method of hemostasis utilizing various agents such as gelfoam, silastic, metal, glass, or plastic pellets, autologous clot, fat, and muscle as emboli. It has been used in the treatment of spinal cord and intracranial arteriovenous malformations, renal arteriovenous fistulas, gastrointestinal bleeding, epistaxis, hypersplenism, certain highly vascular tumors, traumatic rupture of blood vessels, and control of operative hemorrhage. Gastrointestinal Bleeding (stroke/ transient ischemic attack Transient ischemic attack Transient ischemic attack (TIA) is a temporary episode of neurologic dysfunction caused by ischemia without infarction that resolves completely when blood supply is restored. Transient ischemic attack is a neurologic emergency that warrants urgent medical attention. Transient Ischemic Attack (TIA) [ TIA TIA Transient ischemic attack (TIA) is a temporary episode of neurologic dysfunction caused by ischemia without infarction that resolves completely when blood supply is restored. Transient ischemic attack is a neurologic emergency that warrants urgent medical attention. Transient Ischemic Attack (TIA)] presenting with focal neurologic deficits Neurologic Deficits High-Risk Headaches such as paresis Paresis A general term referring to a mild to moderate degree of muscular weakness, occasionally used as a synonym for paralysis (severe or complete loss of motor function). In the older literature, paresis often referred specifically to paretic neurosyphilis. ‘general paresis’ and ‘general paralysis’ may still carry that connotation. Bilateral lower extremity paresis is referred to as paraparesis. Spinal Disk Herniation, vision Vision Ophthalmic Exam loss, or renal, splenic, or intestinal infarct Infarct Area of necrotic cells in an organ, arising mainly from hypoxia and ischemia Ischemic Cell Damage)

Diagnosis

Available tests

The following list outlines the tests available in detecting and evaluating atrial fibrillation Atrial fibrillation Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation (with the 1st tests being cardiac-focused). Note that presenting symptoms vary, so in some cases, noncardiac tests are performed initially.

Electrocardiogram Electrocardiogram An electrocardiogram (ECG) is a graphic representation of the electrical activity of the heart plotted against time. Adhesive electrodes are affixed to the skin surface allowing measurement of cardiac impulses from many angles. The ECG provides 3-dimensional information about the conduction system of the heart, the myocardium, and other cardiac structures. Electrocardiogram (ECG) ( ECG ECG An electrocardiogram (ECG) is a graphic representation of the electrical activity of the heart plotted against time. Adhesive electrodes are affixed to the skin surface allowing measurement of cardiac impulses from many angles. The ECG provides 3-dimensional information about the conduction system of the heart, the myocardium, and other cardiac structures. Electrocardiogram (ECG)): confirms diagnosis^[1,4,14,21]

• Irregularly irregular (pathognomonic)
• RR RR Relative risk (RR) is the risk of a disease or condition occurring in a group or population with a particular exposure relative to a control (unexposed) group. Measures of Risk intervals follow no repetitive pattern
• No distinct P waves
• Narrow QRS complexes (< 0.12 seconds)

Ambulatory monitoring:^[1,14]

• 24–48-hour ambulatory (Holter) monitor:
  • Use if symptoms occur daily or almost daily
  • Also used to determine ventricular control
• Patch Patch Nonpalpable lesion > 1 cm in diameter Generalized and Localized Rashes monitor:
  • Adhesive device without leads, wires, or battery packs, making testing convenient
  • Single lead only
  • Able to record up to 14 days
• Event monitor:
  • Use if symptoms occur less frequently (e.g., weekly or monthly)
  • Data are saved when the individual pushes the event button.
  • Some advanced recorders have an auto-detect feature that records even when there are no symptoms.
• Mobile cardiac outpatient telemetry Telemetry Transmission of the readings of instruments to a remote location by means of wires, radio waves, or other means. Crush Syndrome (MCOT):
  • Use if symptoms occur less frequently (e.g., weekly or monthly)
  • Worn up to 30 days
  • Evaluates AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation as a possible cause of cryptogenic stroke Cryptogenic Stroke Patent Foramen Ovale (such as in subclinical AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation)
• Insertable cardiac monitors (implantable cardiac monitor or implantable loop recorder):
  • Symptoms are suspicious for arrhythmia and pose a danger to the individual (e.g., syncope Syncope Syncope is a short-term loss of consciousness and loss of postural stability followed by spontaneous return of consciousness to the previous neurologic baseline without the need for resuscitation. The condition is caused by transient interruption of cerebral blood flow that may be benign or related to a underlying life-threatening condition. Syncope) but the Holter monitor and/or event recorder have not been revealing.
  • Implanted in the left pectoral region
  • Can last 2–4 years, depending on manufacturer

Echocardiography Echocardiography Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues. The standard approach is transthoracic. Tricuspid Valve Atresia (TVA): used to identify etiology and complications, not for diagnosis

• Transthoracic echocardiography Transthoracic Echocardiography Imaging of the Heart and Great Vessels ( TTE TTE Imaging of the Heart and Great Vessels):
  • Used to assess cardiac function
  • Rules out or confirms structural cardiac disease (e.g., valve stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS))
  • Evaluates size of chambers (atria and ventricles):
    • Left atrial enlargement (LAE) is common in AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation (particularly in hypertension Hypertension Hypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter. Hypertension, mitral valve Mitral valve The valve between the left atrium and left ventricle of the heart. Heart: Anatomy disease).
    • Presence of LAE indicates decreased probability Probability Probability is a mathematical tool used to study randomness and provide predictions about the likelihood of something happening. There are several basic rules of probability that can be used to help determine the probability of multiple events happening together, separately, or sequentially. Basics of Probability of maintaining sinus rhythm Sinus rhythm A heart rate and rhythm driven by the regular firing of the SA node (60–100 beats per minute) Cardiac Physiology.
  • Assesses mitral valve Mitral valve The valve between the left atrium and left ventricle of the heart. Heart: Anatomy anatomy and function (mitral stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS) or regurgitation Regurgitation Gastroesophageal Reflux Disease (GERD), both of which can present as AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation)
  • Can possibly detect left atrial thrombus
• Transesophageal echocardiogram Echocardiogram Transposition of the Great Vessels ( TEE TEE Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues using a transducer placed in the esophagus. Imaging of the Heart and Great Vessels):
  • Rules out or confirms the structural cardiac disease
  • Indicated if AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation lasted for > 48 hrs HRS Hepatorenal syndrome (HRS) is a potentially reversible cause of acute kidney injury that develops secondary to liver disease. The main cause of hrs is hypovolemia, often as a result of forced diuresis or drainage of ascites. This leads to renal vasoconstriction resulting in hypoperfusion of the kidneys. Hepatorenal Syndrome or if the duration is unknown
  • Indicated if planning cardioversion Cardioversion Atrial Fibrillation on patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship who haven’t received anticoagulation Anticoagulation Pulmonary Hypertension Drugs (AC) therapy for at least 3 weeks
  • Used to detect thrombi within the left atrium or left atrial appendage
    • More sensitive than TTE TTE Imaging of the Heart and Great Vessels in detecting thrombus
    • Spontaneous echo contrast (“smoke”), smoke-like echoes (representing preceding stage of thrombus formation) in the LA, can be seen 
    • Blood flow velocity Flow velocity Vascular Resistance, Flow, and Mean Arterial Pressure is also detected (lower flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure → stasis and thrombus formation)

Additional testing^[1,21]

Other tests to rule out underlying and predisposing conditions.

Laboratory studies:

• CBC → infection/ sepsis Sepsis Systemic inflammatory response syndrome with a proven or suspected infectious etiology. When sepsis is associated with organ dysfunction distant from the site of infection, it is called severe sepsis. When sepsis is accompanied by hypotension despite adequate fluid infusion, it is called septic shock. Sepsis and Septic Shock
• BUN, creatinine → kidney function
• Electrolytes Electrolytes Electrolytes are mineral salts that dissolve in water and dissociate into charged particles called ions, which can be either be positively (cations) or negatively (anions) charged. Electrolytes are distributed in the extracellular and intracellular compartments in different concentrations. Electrolytes are essential for various basic life-sustaining functions. Electrolytes ( potassium Potassium An element in the alkali group of metals with an atomic symbol k, atomic number 19, and atomic weight 39. 10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the water-electrolyte balance. Hyperkalemia, calcium Calcium A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes. Electrolytes, or magnesium Magnesium A metallic element that has the atomic symbol mg, atomic number 12, and atomic weight 24. 31. It is important for the activity of many enzymes, especially those involved in oxidative phosphorylation. Electrolytes) → electrolyte imbalances
• Cardiac enzymes Enzymes Enzymes are complex protein biocatalysts that accelerate chemical reactions without being consumed by them. Due to the body’s constant metabolic needs, the absence of enzymes would make life unsustainable, as reactions would occur too slowly without these molecules. Basics of Enzymes → myocardial infarction Myocardial infarction MI is ischemia and death of an area of myocardial tissue due to insufficient blood flow and oxygenation, usually from thrombus formation on a ruptured atherosclerotic plaque in the epicardial arteries. Clinical presentation is most commonly with chest pain, but women and patients with diabetes may have atypical symptoms. Myocardial Infarction
• BNP BNP A peptide that is secreted by the brain and the heart atria, stored mainly in cardiac ventricular myocardium. It can cause natriuresis; diuresis; vasodilation; and inhibits secretion of renin and aldosterone. It improves heart function. It contains 32 amino acids. Renal Sodium and Water Regulation → heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR)
• TSH/fT4 → hyperthyroidism Hyperthyroidism Hypersecretion of thyroid hormones from the thyroid gland. Elevated levels of thyroid hormones increase basal metabolic rate. Thyrotoxicosis and Hyperthyroidism
• HbA_1c → diabetes Diabetes Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance. Diabetes Mellitus 
• D-dimer D-dimer Deep Vein Thrombosis → venous thromboembolism Thromboembolism Obstruction of a blood vessel (embolism) by a blood clot (thrombus) in the blood stream. Systemic Lupus Erythematosus
• Urine drug screen → cocaine Cocaine An alkaloid ester extracted from the leaves of plants including coca. It is a local anesthetic and vasoconstrictor and is clinically used for that purpose, particularly in the eye, ear, nose, and throat. It also has powerful central nervous system effects similar to the amphetamines and is a drug of abuse. Cocaine, like amphetamines, acts by multiple mechanisms on brain catecholaminergic neurons; the mechanism of its reinforcing effects is thought to involve inhibition of dopamine uptake. Local Anesthetics, amphetamines Amphetamines Analogs or derivatives of amphetamine. Many are sympathomimetics and central nervous system stimulators causing excitation, vasopressin, bronchodilation, and to varying degrees, anorexia, analepsis, nasal decongestion, and some smooth muscle relaxation. Stimulants, digoxin Digoxin A cardiotonic glycoside obtained mainly from digitalis lanata; it consists of three sugars and the aglycone digoxigenin. Digoxin has positive inotropic and negative chronotropic activity. It is used to control ventricular rate in atrial fibrillation and in the management of congestive heart failure with atrial fibrillation. Its use in congestive heart failure and sinus rhythm is less certain. The margin between toxic and therapeutic doses is small. Cardiac Glycosides, or alcohol

Imaging and procedures:

• Chest X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests → pulmonary disease Pulmonary disease Diseases involving the respiratory system. Blastomyces/Blastomycosis/conditions, heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR)
• CT pulmonary angiography Angiography Radiography of blood vessels after injection of a contrast medium. Cardiac Surgery → pulmonary embolism Pulmonary Embolism Pulmonary embolism (PE) is a potentially fatal condition that occurs as a result of intraluminal obstruction of the main pulmonary artery or its branches. The causative factors include thrombi, air, amniotic fluid, and fat. In PE, gas exchange is impaired due to the decreased return of deoxygenated blood to the lungs. Pulmonary Embolism
• Exercise testing → ischemic heart disease Ischemic heart disease Coronary heart disease (CHD), or ischemic heart disease, describes a situation in which an inadequate supply of blood to the myocardium exists due to a stenosis of the coronary arteries, typically from atherosclerosis. Coronary Heart Disease, also guides pharmacotherapy
• Sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep study → obstructive sleep apnea Sleep apnea Repeated cessation of breathing for > 10 seconds during sleep and results in sleep interruption, fatigue, and daytime sleepiness. Obstructive Sleep Apnea 
• Cardiac catheterization Cardiac Catheterization Procedures in which placement of cardiac catheters is performed for therapeutic or diagnostic procedures. Cardiac Surgery → coronary artery Coronary Artery Truncus Arteriosus disease, ischemia Ischemia A hypoperfusion of the blood through an organ or tissue caused by a pathologic constriction or obstruction of its blood vessels, or an absence of blood circulation. Ischemic Cell Damage

Testing approach (new-onset AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation)^[1,4,10,14]

• For hemodynamically unstable individuals:
  • Diagnosis and treatment are done simultaneously.
  • Seen in emergency department settings or during hospitalizations (for cardiac, noncardiac, or surgical conditions)
  • AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation is detected either through ECG ECG An electrocardiogram (ECG) is a graphic representation of the electrical activity of the heart plotted against time. Adhesive electrodes are affixed to the skin surface allowing measurement of cardiac impulses from many angles. The ECG provides 3-dimensional information about the conduction system of the heart, the myocardium, and other cardiac structures. Electrocardiogram (ECG) or on telemetry Telemetry Transmission of the readings of instruments to a remote location by means of wires, radio waves, or other means. Crush Syndrome. 
• For hemodynamically stable individuals (no or minimal symptoms):
  • Detection:
    • Often, AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation is detected incidentally through ECG ECG An electrocardiogram (ECG) is a graphic representation of the electrical activity of the heart plotted against time. Adhesive electrodes are affixed to the skin surface allowing measurement of cardiac impulses from many angles. The ECG provides 3-dimensional information about the conduction system of the heart, the myocardium, and other cardiac structures. Electrocardiogram (ECG) or ambulatory monitoring (obtained for other reasons). 
    • Irregular pulses can also be noted on manual pulse palpation Palpation Application of fingers with light pressure to the surface of the body to determine consistency of parts beneath in physical diagnosis; includes palpation for determining the outlines of organs. Dermatologic Examination by the clinician Clinician A physician, nurse practitioner, physician assistant, or another health professional who is directly involved in patient care and has a professional relationship with patients. Clinician–Patient Relationship.
  • Obtain old records (e.g., prior ECGs, if available)
  • Review current ECG ECG An electrocardiogram (ECG) is a graphic representation of the electrical activity of the heart plotted against time. Adhesive electrodes are affixed to the skin surface allowing measurement of cardiac impulses from many angles. The ECG provides 3-dimensional information about the conduction system of the heart, the myocardium, and other cardiac structures. Electrocardiogram (ECG)
  • Laboratory tests:
    • In general, includes CBC, metabolic panel with renal function, and thyroid Thyroid The thyroid gland is one of the largest endocrine glands in the human body. The thyroid gland is a highly vascular, brownish-red gland located in the visceral compartment of the anterior region of the neck. Thyroid Gland: Anatomy tests
    • Additional tests as indicated by underlying and suspected conditions 
  • TTE TTE Imaging of the Heart and Great Vessels to evaluate associated cardiac disease
  • Additional imaging, depending on presentation (e.g., chest X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests)
  • Discussion includes:
    • Natural progression of AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation
    • Need for rate control and possible cardioversion Cardioversion Atrial Fibrillation
    • Stroke risk and long-term AC
    • Signs and symptoms (e.g., palpitations Palpitations Ebstein’s Anomaly, syncope Syncope Syncope is a short-term loss of consciousness and loss of postural stability followed by spontaneous return of consciousness to the previous neurologic baseline without the need for resuscitation. The condition is caused by transient interruption of cerebral blood flow that may be benign or related to a underlying life-threatening condition. Syncope) to watch out for

Management

Variation in guidelines can be seen based on practice locations and availability of resources and drugs. Detailed information regarding regional recommendations is available for review (US, UK, Europe) as well as a comparison summary of the global recommendations.

Overview

Care for individuals with AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation involves addressing the acute onset of AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation (new onset or uncontrolled rate), control of chronic arrhythmia, and reduction of associated risks.

AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation management consists of the following:

• Determination of hemodynamic status
• Rate control OR rhythm control
• AC therapy
• Treatment of the underlying cause

Special considerations:

• Newly discovered AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation < 24–48 hours → electrical cardioversion Cardioversion Atrial Fibrillation (can be performed without AC)
• If concurrent WPW syndrome → IV procainamide Procainamide A class ia antiarrhythmic drug that is structurally-related to procaine. Class 1 Antiarrhythmic Drugs (Sodium Channel Blockers) or IV ibutilide Ibutilide Class 3 Antiarrhythmic Drugs (Potassium Channel Blockers) 
• Ablative therapy and left atrial appendage occlusion are other nonpharmacologic AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation treatment options.

Acute management^{[1,3,12,14,15]}

Acute management has the following main components: controlling the ventricular response (VR) and determining the need for cardioversion Cardioversion Atrial Fibrillation.

• Hemodynamically unstable: 
  • In acute hypotension Hypotension Hypotension is defined as low blood pressure, specifically < 90/60 mm Hg, and is most commonly a physiologic response. Hypotension may be mild, serious, or life threatening, depending on the cause. Hypotension, heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR), MI MI MI is ischemia and death of an area of myocardial tissue due to insufficient blood flow and oxygenation, usually from thrombus formation on a ruptured atherosclerotic plaque in the epicardial arteries. Clinical presentation is most commonly with chest pain, but women and patients with diabetes may have atypical symptoms. Myocardial Infarction, altered mental status Altered Mental Status Sepsis in Children due to AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation with rapid VR (> 110/min) → emergent cardioversion Cardioversion Atrial Fibrillation
    • Sedation and analgesia Analgesia Methods of pain relief that may be used with or in place of analgesics. Anesthesiology: History and Basic Concepts required
    • Anticoagulation Anticoagulation Pulmonary Hypertension Drugs given (unless previously treated with oral anticoagulant therapy)
    • Synchronized cardioversion Synchronized cardioversion Atrial Flutter: biphasic direct current shock Shock Shock is a life-threatening condition associated with impaired circulation that results in tissue hypoxia. The different types of shock are based on the underlying cause: distributive (↑ cardiac output (CO), ↓ systemic vascular resistance (SVR)), cardiogenic (↓ CO, ↑ SVR), hypovolemic (↓ CO, ↑ SVR), obstructive (↓ CO), and mixed. Types of Shock is performed (generally starting at 100 to 150 joules). 
    • Maximum of 2 additional shocks (increasing energy) 
    • Successful treatment → sinus rhythm Sinus rhythm A heart rate and rhythm driven by the regular firing of the SA node (60–100 beats per minute) Cardiac Physiology
  • If slow or moderate VR (< 110/min) is noted, other etiologies should be investigated as the cause of clinical instability.
• Hemodynamically stable:
  • Control heart rate Heart rate The number of times the heart ventricles contract per unit of time, usually per minute. Cardiac Physiology and symptoms with:
    • IV beta-blockers Beta-blockers Drugs that bind to but do not activate beta-adrenergic receptors thereby blocking the actions of beta-adrenergic agonists. Adrenergic beta-antagonists are used for treatment of hypertension, cardiac arrhythmias, angina pectoris, glaucoma, migraine headaches, and anxiety. Class 2 Antiarrhythmic Drugs (Beta Blockers): metoprolol Metoprolol A selective adrenergic beta-1 blocking agent that is commonly used to treat angina pectoris; hypertension; and cardiac arrhythmias. Antiadrenergic Drugs, propranolol Propranolol A widely used non-cardioselective beta-adrenergic antagonist. Propranolol has been used for myocardial infarction; arrhythmia; angina pectoris; hypertension; hyperthyroidism; migraine; pheochromocytoma; and anxiety but adverse effects instigate replacement by newer drugs. Antiadrenergic Drugs, or esmolol Esmolol Antiadrenergic Drugs
    • IV CCB: diltiazem Diltiazem A benzothiazepine derivative with vasodilating action due to its antagonism of the actions of calcium ion on membrane functions. Class 4 Antiarrhythmic Drugs (Calcium Channel Blockers) or verapamil Verapamil A calcium channel blocker that is a class IV anti-arrhythmia agent. Pulmonary Hypertension Drugs
    • IV digoxin Digoxin A cardiotonic glycoside obtained mainly from digitalis lanata; it consists of three sugars and the aglycone digoxigenin. Digoxin has positive inotropic and negative chronotropic activity. It is used to control ventricular rate in atrial fibrillation and in the management of congestive heart failure with atrial fibrillation. Its use in congestive heart failure and sinus rhythm is less certain. The margin between toxic and therapeutic doses is small. Cardiac Glycosides: 2nd line
    • IV amiodarone Amiodarone An antianginal and class III antiarrhythmic drug. It increases the duration of ventricular and atrial muscle action by inhibiting potassium channels and voltage-gated sodium channels. There is a resulting decrease in heart rate and in vascular resistance. Pulmonary Fibrosis: 2nd line
  • Identify and treat precipitating conditions/factors.
  • Stability allows time to plan subsequent management:
    • Determine long-term management (rate versus rhythm control)
    • Prevent thromboembolism Thromboembolism Obstruction of a blood vessel (embolism) by a blood clot (thrombus) in the blood stream. Systemic Lupus Erythematosus (use anticoagulation Anticoagulation Pulmonary Hypertension Drugs).

Subsequent management^[1,3]

• Majority of those presenting with stable vital signs (new-onset or known AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation) will need rate control first.
• Choice of rate versus rhythm control for long-term treatment:
  • Consider the following factors (among others): cardiovascular risks, symptoms, AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation duration
  • Choosing rate control:
    • Historically preferred for individuals > 80 years (as AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation is often permanent and/or asymptomatic in this group)
    • Long-standing AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation
    • Asymptomatic AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation
  • Choosing rhythm control ( cardioversion Cardioversion Atrial Fibrillation):
    • Has been shown to improve survival in those > 75 years of age with CV CV Vasculitides risks (e.g., DM DM Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance. Diabetes Mellitus, heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR), CAD), if performed within 12 months¹³
    • Persistent symptoms despite rate control
    • Younger individuals (< 65 years of age)

Rate control^[1,3,14]

Background:

• Slowing of conduction through the atrioventricular node Atrioventricular node A small nodular mass of specialized muscle fibers located in the interatrial septum near the opening of the coronary sinus. It gives rise to the atrioventricular bundle of the conduction system of the heart. Heart: Anatomy
• Persistently elevated ventricular rates can lead to cardiomyopathy Cardiomyopathy Cardiomyopathy refers to a group of myocardial diseases associated with structural changes of the heart muscles (myocardium) and impaired systolic and/or diastolic function in the absence of other heart disorders (coronary artery disease, hypertension, valvular disease, and congenital heart disease). Cardiomyopathy: Overview and Types, so it is important to maintain rate control.
• Goal:^[25]
  • Control symptoms
  • HR < 110/min in asymptomatic AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation
  • HR < 80/min in symptomatic AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation

Medications:

• 1st-line:
  • Beta-blockers Beta-blockers Drugs that bind to but do not activate beta-adrenergic receptors thereby blocking the actions of beta-adrenergic agonists. Adrenergic beta-antagonists are used for treatment of hypertension, cardiac arrhythmias, angina pectoris, glaucoma, migraine headaches, and anxiety. Class 2 Antiarrhythmic Drugs (Beta Blockers) (e.g., atenolol Atenolol A cardioselective beta-1 adrenergic blocker possessing properties and potency similar to propranolol, but without a negative inotropic effect. Class 2 Antiarrhythmic Drugs (Beta Blockers), metoprolol Metoprolol A selective adrenergic beta-1 blocking agent that is commonly used to treat angina pectoris; hypertension; and cardiac arrhythmias. Antiadrenergic Drugs, esmolol Esmolol Antiadrenergic Drugs)
    • Available oral drugs have a long half-life Half-Life The time it takes for a substance (drug, radioactive nuclide, or other) to lose half of its pharmacologic, physiologic, or radiologic activity. Pharmacokinetics and Pharmacodynamics, allowing for convenient dosing.
    • Beneficial for CAD and chronic heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR) with systolic dysfunction Systolic dysfunction Dilated Cardiomyopathy (not acute exacerbation)
  • Nondihydropyridine CCB (e.g., diltiazem Diltiazem A benzothiazepine derivative with vasodilating action due to its antagonism of the actions of calcium ion on membrane functions. Class 4 Antiarrhythmic Drugs (Calcium Channel Blockers), verapamil Verapamil A calcium channel blocker that is a class IV anti-arrhythmia agent. Pulmonary Hypertension Drugs):
    • Have negative inotropic effects
    • Not given in New York Heart Association functional class III or IV, preexcitation syndrome, or significant hypotension Hypotension Hypotension is defined as low blood pressure, specifically < 90/60 mm Hg, and is most commonly a physiologic response. Hypotension may be mild, serious, or life threatening, depending on the cause. Hypotension
• 2nd-line:
  • Digoxin Digoxin A cardiotonic glycoside obtained mainly from digitalis lanata; it consists of three sugars and the aglycone digoxigenin. Digoxin has positive inotropic and negative chronotropic activity. It is used to control ventricular rate in atrial fibrillation and in the management of congestive heart failure with atrial fibrillation. Its use in congestive heart failure and sinus rhythm is less certain. The margin between toxic and therapeutic doses is small. Cardiac Glycosides:
    • Less effective than the first 2 drugs
    • Option if AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation not adequately controlled with beta-blocker and/or CCB
    • Has positive inotropic effect, which may be helpful in heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR) with reduced ejection fraction Ejection fraction Cardiac Cycle
    • Less hypotensive effect than beta-blockers Beta-blockers Drugs that bind to but do not activate beta-adrenergic receptors thereby blocking the actions of beta-adrenergic agonists. Adrenergic beta-antagonists are used for treatment of hypertension, cardiac arrhythmias, angina pectoris, glaucoma, migraine headaches, and anxiety. Class 2 Antiarrhythmic Drugs (Beta Blockers) and CCBs CCBs Calcium channel blockers (CCBS) are a class of medications that inhibit voltage-dependent L-type calcium channels of cardiac and vascular smooth muscle cells. The inhibition of these channels produces vasodilation and myocardial depression. There are 2 major classes of CCBS: dihydropyridines and non-dihydropyridines. Class 4 Antiarrhythmic Drugs (Calcium Channel Blockers) → can be useful for acute management of critically ill patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship
    • Periodic monitoring of drug level needed (narrow therapeutic window Therapeutic Window Dosage Calculation)
  • Amiodarone Amiodarone An antianginal and class III antiarrhythmic drug. It increases the duration of ventricular and atrial muscle action by inhibiting potassium channels and voltage-gated sodium channels. There is a resulting decrease in heart rate and in vascular resistance. Pulmonary Fibrosis:
    • Used for maintenance of sinus rhythm Sinus rhythm A heart rate and rhythm driven by the regular firing of the SA node (60–100 beats per minute) Cardiac Physiology, but also reduces ventricular rate
    • Less hypotensive effect than beta-blockers Beta-blockers Drugs that bind to but do not activate beta-adrenergic receptors thereby blocking the actions of beta-adrenergic agonists. Adrenergic beta-antagonists are used for treatment of hypertension, cardiac arrhythmias, angina pectoris, glaucoma, migraine headaches, and anxiety. Class 2 Antiarrhythmic Drugs (Beta Blockers) and CCBs CCBs Calcium channel blockers (CCBS) are a class of medications that inhibit voltage-dependent L-type calcium channels of cardiac and vascular smooth muscle cells. The inhibition of these channels produces vasodilation and myocardial depression. There are 2 major classes of CCBS: dihydropyridines and non-dihydropyridines. Class 4 Antiarrhythmic Drugs (Calcium Channel Blockers) → can be useful for acute management of critically ill patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship
    • Beware of potential for cardioversion Cardioversion Atrial Fibrillation → can lead to stroke in patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship not on proper anticoagulation Anticoagulation Pulmonary Hypertension Drugs
    • Has a delayed onset of action
    • Often avoided due to potential side effects and toxicity Toxicity Dosage Calculation
    • Not recommended in UK^[14]
• In AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation with WPW pattern:^[25] 
  • Avoid beta-blockers Beta-blockers Drugs that bind to but do not activate beta-adrenergic receptors thereby blocking the actions of beta-adrenergic agonists. Adrenergic beta-antagonists are used for treatment of hypertension, cardiac arrhythmias, angina pectoris, glaucoma, migraine headaches, and anxiety. Class 2 Antiarrhythmic Drugs (Beta Blockers), CCB, digoxin Digoxin A cardiotonic glycoside obtained mainly from digitalis lanata; it consists of three sugars and the aglycone digoxigenin. Digoxin has positive inotropic and negative chronotropic activity. It is used to control ventricular rate in atrial fibrillation and in the management of congestive heart failure with atrial fibrillation. Its use in congestive heart failure and sinus rhythm is less certain. The margin between toxic and therapeutic doses is small. Cardiac Glycosides, and amiodarone Amiodarone An antianginal and class III antiarrhythmic drug. It increases the duration of ventricular and atrial muscle action by inhibiting potassium channels and voltage-gated sodium channels. There is a resulting decrease in heart rate and in vascular resistance. Pulmonary Fibrosis.
  • These medications have potential to lead to ventricular arrhythmias and cardiac arrest Cardiac arrest Cardiac arrest is the sudden, complete cessation of cardiac output with hemodynamic collapse. Patients present as pulseless, unresponsive, and apneic. Rhythms associated with cardiac arrest are ventricular fibrillation/tachycardia, asystole, or pulseless electrical activity. Cardiac Arrest.

Rhythm control^{[1,3,14,15,21]}

Cardioversion Cardioversion Atrial Fibrillation, and subsequent maintenance of sinus rhythm Sinus rhythm A heart rate and rhythm driven by the regular firing of the SA node (60–100 beats per minute) Cardiac Physiology, should be managed under the guidance of a cardiologist.

• Types of cardioversion Cardioversion Atrial Fibrillation:
  • Electrical cardioversion Cardioversion Atrial Fibrillation:
    • Preferred for the 1st AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation episode
    • Better efficacy but requires sedation
  • Pharmacologic cardioversion Pharmacologic cardioversion Atrial Flutter:
    • Carries risk of proarrhythmic effects of drugs
    • In general, requires prolonged telemetry Telemetry Transmission of the readings of instruments to a remote location by means of wires, radio waves, or other means. Crush Syndrome monitoring
    • Medication options include flecainide Flecainide A potent anti-arrhythmia agent, effective in a wide range of ventricular and atrial arrhythmias and tachycardias. Class 1 Antiarrhythmic Drugs (Sodium Channel Blockers), propafenone Propafenone An antiarrhythmic agent that is particularly effective in ventricular arrhythmias. It also has weak beta-blocking activity. Class 1 Antiarrhythmic Drugs (Sodium Channel Blockers), dofetilide Dofetilide Class 3 Antiarrhythmic Drugs (Potassium Channel Blockers), amiodarone Amiodarone An antianginal and class III antiarrhythmic drug. It increases the duration of ventricular and atrial muscle action by inhibiting potassium channels and voltage-gated sodium channels. There is a resulting decrease in heart rate and in vascular resistance. Pulmonary Fibrosis, ibutilide Ibutilide Class 3 Antiarrhythmic Drugs (Potassium Channel Blockers), and vernakalant (in Europe and Canada)
    • “Pill in a pocket”: flecainide Flecainide A potent anti-arrhythmia agent, effective in a wide range of ventricular and atrial arrhythmias and tachycardias. Class 1 Antiarrhythmic Drugs (Sodium Channel Blockers) or propafenone Propafenone An antiarrhythmic agent that is particularly effective in ventricular arrhythmias. It also has weak beta-blocking activity. Class 1 Antiarrhythmic Drugs (Sodium Channel Blockers) given in monitored outpatient setting in select cases
• AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation > 48 hours or unknown duration or high risk of stroke (such as mechanical valve or rheumatic mitral stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS), prior thromboembolism Thromboembolism Obstruction of a blood vessel (embolism) by a blood clot (thrombus) in the blood stream. Systemic Lupus Erythematosus):
  • Anticoagulation Anticoagulation Pulmonary Hypertension Drugs approach:
    • At least 3 weeks of AC (regardless of the CHA₂DS₂-VASc score) prior to planned cardioversion Cardioversion Atrial Fibrillation 
    •  4 weeks of AC after procedure
  • TEE-based approach:
    • An option for those with significant symptoms and/or with high risk of bleeding)
    • Shorter duration of anticoagulation Anticoagulation Pulmonary Hypertension Drugs
    • TEE TEE Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues using a transducer placed in the esophagus. Imaging of the Heart and Great Vessels performed, looking for thrombus in the right and left atria (site for most of the thrombi)
    • No thrombus → cardioversion Cardioversion Atrial Fibrillation + 4 weeks of AC after the procedure
    • With thrombus → NO cardioversion Cardioversion Atrial Fibrillation; AC for ≥ 4 weeks and repeat TEE TEE Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues using a transducer placed in the esophagus. Imaging of the Heart and Great Vessels on follow-up to check for thrombus
• AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation < 48 hours or have been on AC for > 3 weeks:
  • In some practices, no AC is given before cardioversion Cardioversion Atrial Fibrillation, especially if AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation is < 24 hours and stroke risk is low.
  • However, in cases with high stroke risk, AC is given for a few hours prior to cardioversion Cardioversion Atrial Fibrillation.
  • Continue AC, if already present, then proceed with cardioversion Cardioversion Atrial Fibrillation.
• Medications used for the maintenance of sinus rhythm Sinus rhythm A heart rate and rhythm driven by the regular firing of the SA node (60–100 beats per minute) Cardiac Physiology after cardioversion Cardioversion Atrial Fibrillation include:
  • Amiodarone Amiodarone An antianginal and class III antiarrhythmic drug. It increases the duration of ventricular and atrial muscle action by inhibiting potassium channels and voltage-gated sodium channels. There is a resulting decrease in heart rate and in vascular resistance. Pulmonary Fibrosis
  • Dofetilide Dofetilide Class 3 Antiarrhythmic Drugs (Potassium Channel Blockers)
  • Dronedarone Dronedarone A non-iodinated derivative of amiodarone that is used for the treatment of arrhythmia. Class 3 Antiarrhythmic Drugs (Potassium Channel Blockers)
  • Flecainide Flecainide A potent anti-arrhythmia agent, effective in a wide range of ventricular and atrial arrhythmias and tachycardias. Class 1 Antiarrhythmic Drugs (Sodium Channel Blockers)
  • Propafenone Propafenone An antiarrhythmic agent that is particularly effective in ventricular arrhythmias. It also has weak beta-blocking activity. Class 1 Antiarrhythmic Drugs (Sodium Channel Blockers)
  • Sotalol Sotalol An adrenergic beta-antagonist that is used in the treatment of life-threatening arrhythmias. Class 3 Antiarrhythmic Drugs (Potassium Channel Blockers)
• On follow-up:
  • Long-term AC is determined by thromboembolic and bleeding risk (see Anticoagulation Anticoagulation Pulmonary Hypertension Drugs section below).
  • Frequently, in cases of underlying cardiac disease, maintenance antiarrhythmics are needed after cardioversion Cardioversion Atrial Fibrillation.

Anticoagulation Anticoagulation Pulmonary Hypertension Drugs^{[1,3,14,15,21,23]}

The use of anticoagulation Anticoagulation Pulmonary Hypertension Drugs should be based on the patient’s risk factors for thromboembolism Thromboembolism Obstruction of a blood vessel (embolism) by a blood clot (thrombus) in the blood stream. Systemic Lupus Erythematosus and bleeding, but should account for their personal preferences. These factors should be reevaluated periodically.

Is anticoagulation Anticoagulation Pulmonary Hypertension Drugs appropriate?

• Determine if AC is recommended by checking the risk for thromboembolism Thromboembolism Obstruction of a blood vessel (embolism) by a blood clot (thrombus) in the blood stream. Systemic Lupus Erythematosus (CHA₂DS₂-VASc score):^[14,21]
  • Score of  ≥ 2 in men or ≥ 3 in women: long-term oral anticoagulants Anticoagulants Anticoagulants are drugs that retard or interrupt the coagulation cascade. The primary classes of available anticoagulants include heparins, vitamin K-dependent antagonists (e.g., warfarin), direct thrombin inhibitors, and factor Xa inhibitors. Anticoagulants (OAC)
  • Score of 1 in men and 2 in women (1 nonsex risk factor with a value of 1): consider long-term OAC
  • Score of 0 in men or 1 in women (except moderate-to-severe mitral stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS), mechanical heart valve): no long-term OAC
• Check for contraindications Contraindications A condition or factor associated with a recipient that makes the use of a drug, procedure, or physical agent improper or inadvisable. Contraindications may be absolute (life threatening) or relative (higher risk of complications in which benefits may outweigh risks). Noninvasive Ventilation for AC (e.g., active or recent severe bleeding, severe thrombocytopenia Severe Thrombocytopenia Thrombocytopenia).
• Assess the risk of bleeding:
  • HAS-BLED score (calculator) provides a risk estimate for major bleeding.
  • UK: ORBIT bleeding risk score (calculator)^[14]
• Note: The type of AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation (e.g., paroxysmal, persistent) does not factor into the decision about anticoagulation Anticoagulation Pulmonary Hypertension Drugs.

If appropriate, pick an agent:

• Options:
  • Direct oral anticoagulants Anticoagulants Anticoagulants are drugs that retard or interrupt the coagulation cascade. The primary classes of available anticoagulants include heparins, vitamin K-dependent antagonists (e.g., warfarin), direct thrombin inhibitors, and factor Xa inhibitors. Anticoagulants ( DOACs DOACs Anticoagulants), also known as novel oral anticoagulants Anticoagulants Anticoagulants are drugs that retard or interrupt the coagulation cascade. The primary classes of available anticoagulants include heparins, vitamin K-dependent antagonists (e.g., warfarin), direct thrombin inhibitors, and factor Xa inhibitors. Anticoagulants (NOACs) or:
    • Factor Xa inhibitors: apixaban Apixaban Anticoagulants, edoxaban Edoxaban Anticoagulants, rivaroxaban Rivaroxaban A morpholine and thiophene derivative that functions as a factor Xa inhibitor and is used in the treatment and prevention of deep-vein thrombosis and pulmonary embolism. It is also used for the prevention of stroke and systemic embolization in patients with non-valvular atrial fibrillation, and for the prevention of atherothrombotic events in patients after an acute coronary syndrome. Anticoagulants
    • Direct thrombin inhibitor Direct Thrombin Inhibitor Anticoagulants: dabigatran Dabigatran A thrombin inhibitor which acts by binding and blocking thrombogenic activity and the prevention of thrombus formation. It is used to reduce the risk of stroke and systemic embolism in patients with nonvalvular atrial fibrillation. Anticoagulants (150 mg twice a day)
  • Vitamin K Vitamin K A lipid cofactor that is required for normal blood clotting. Several forms of vitamin K have been identified: vitamin K 1 (phytomenadione) derived from plants, vitamin K 2 (menaquinone) from bacteria, and synthetic naphthoquinone provitamins, vitamin K 3 (menadione). Vitamin k 3 provitamins, after being alkylated in vivo, exhibit the antifibrinolytic activity of vitamin k. Green leafy vegetables, liver, cheese, butter, and egg yolk are good sources of vitamin k. Fat-soluble Vitamins and their Deficiencies antagonist: warfarin Warfarin An anticoagulant that acts by inhibiting the synthesis of vitamin K-dependent coagulation factors. Warfarin is indicated for the prophylaxis and/or treatment of venous thrombosis and its extension, pulmonary embolism, and atrial fibrillation with embolization. It is also used as an adjunct in the prophylaxis of systemic embolism after myocardial infarction. Warfarin is also used as a rodenticide. Anticoagulants
• Choosing ACs:
  • DOACs DOACs Anticoagulants:
    • Recommended in most cases
    • Consider switching from warfarin Warfarin An anticoagulant that acts by inhibiting the synthesis of vitamin K-dependent coagulation factors. Warfarin is indicated for the prophylaxis and/or treatment of venous thrombosis and its extension, pulmonary embolism, and atrial fibrillation with embolization. It is also used as an adjunct in the prophylaxis of systemic embolism after myocardial infarction. Warfarin is also used as a rodenticide. Anticoagulants to DOACs DOACs Anticoagulants if there are no contraindications Contraindications A condition or factor associated with a recipient that makes the use of a drug, procedure, or physical agent improper or inadvisable. Contraindications may be absolute (life threatening) or relative (higher risk of complications in which benefits may outweigh risks). Noninvasive Ventilation.
  • Avoid DOACs DOACs Anticoagulants if:
    • Taking medications with potential for drug interactions (e.g., antivirals, P-glycoprotein drug efflux pump Pump ACES and RUSH: Resuscitation Ultrasound Protocols (P-gp) inducers)
    • With creatinine clearance Creatinine clearance Kidney Function Tests (CrCl) < 25 to 30 mL/min
    • Cost of medication is prohibitive.
  • Warfarin Warfarin An anticoagulant that acts by inhibiting the synthesis of vitamin K-dependent coagulation factors. Warfarin is indicated for the prophylaxis and/or treatment of venous thrombosis and its extension, pulmonary embolism, and atrial fibrillation with embolization. It is also used as an adjunct in the prophylaxis of systemic embolism after myocardial infarction. Warfarin is also used as a rodenticide. Anticoagulants is generally recommended in valvular AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation, which is defined as AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation in the setting of:^[29]
    • Mechanical heart valves
    • Moderate-to-severe rheumatic mitral stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS)
    • Further information can be obtained from the 2020 ACC/AHA guideline for management of patients with valvular heart disease
• Additional considerations in AC:
  • Aspirin Aspirin The prototypical analgesic used in the treatment of mild to moderate pain. It has anti-inflammatory and antipyretic properties and acts as an inhibitor of cyclooxygenase which results in the inhibition of the biosynthesis of prostaglandins. Aspirin also inhibits platelet aggregation and is used in the prevention of arterial and venous thrombosis. Nonsteroidal Antiinflammatory Drugs (NSAIDs):
    • Not effective for stroke prevention, even in those with low risk
    • Less effective than OAC, even when combined with clopidogrel Clopidogrel A ticlopidine analog and platelet purinergic p2y receptor antagonist that inhibits adenosine diphosphate-mediated platelet aggregation. It is used to prevent thromboembolism in patients with arterial occlusive diseases; myocardial infarction; stroke; or atrial fibrillation. Antiplatelet Drugs
    • May be given in conjunction with OAC in certain settings (e.g., post– percutaneous coronary intervention Percutaneous coronary intervention A family of percutaneous techniques that are used to manage coronary occlusion, including standard balloon angioplasty (percutaneous transluminal coronary angioplasty), the placement of intracoronary stents, and atheroablative technologies (e.g., atherectomy; endarterectomy; thrombectomy; percutaneous transluminal laser angioplasty). Ptca was the dominant form of pci, before the widespread use of stenting. Cardiac Surgery)
  • DOACs DOACs Anticoagulants:
    • No regular Regular Insulin anticoagulant activity monitoring 
    • Recommended that renal and hepatic levels be checked at least annually
  • Warfarin Warfarin An anticoagulant that acts by inhibiting the synthesis of vitamin K-dependent coagulation factors. Warfarin is indicated for the prophylaxis and/or treatment of venous thrombosis and its extension, pulmonary embolism, and atrial fibrillation with embolization. It is also used as an adjunct in the prophylaxis of systemic embolism after myocardial infarction. Warfarin is also used as a rodenticide. Anticoagulants:
    • INR monitoring required:
      • Goal: between 2–3 (unless other values are indicated by another condition, such as a prosthetic valve Prosthetic Valve Soft Tissue Abscess)
      • Should be checked weekly (at least) during initiation
    • Average annual time in therapeutic range (TTR) should be > 70%.
  • Heparins:
    • Typically an option in the hospital setting (until OAC can be safely initiated)
    • Bridging therapy with warfarin Warfarin An anticoagulant that acts by inhibiting the synthesis of vitamin K-dependent coagulation factors. Warfarin is indicated for the prophylaxis and/or treatment of venous thrombosis and its extension, pulmonary embolism, and atrial fibrillation with embolization. It is also used as an adjunct in the prophylaxis of systemic embolism after myocardial infarction. Warfarin is also used as a rodenticide. Anticoagulants is generally not required unless the patient has a mechanical heart valve or is at a high risk of stroke (always weigh the risk of thrombosis Thrombosis Formation and development of a thrombus or blood clot in the blood vessel. Epidemic Typhus with the risk of bleeding when making a decision).
  • Reversal of anticoagulation Anticoagulation Pulmonary Hypertension Drugs:^[15,23]
    • Idarucizumab Idarucizumab Anticoagulants: dabigatran Dabigatran A thrombin inhibitor which acts by binding and blocking thrombogenic activity and the prevention of thrombus formation. It is used to reduce the risk of stroke and systemic embolism in patients with nonvalvular atrial fibrillation. Anticoagulants reversal in case of life-threatening bleeding or an urgent procedure 
    • Andexanet alfa Andexanet Alfa Anticoagulants: rivaroxaban Rivaroxaban A morpholine and thiophene derivative that functions as a factor Xa inhibitor and is used in the treatment and prevention of deep-vein thrombosis and pulmonary embolism. It is also used for the prevention of stroke and systemic embolization in patients with non-valvular atrial fibrillation, and for the prevention of atherothrombotic events in patients after an acute coronary syndrome. Anticoagulants and apixaban Apixaban Anticoagulants reversal in case of life-threatening or uncontrolled bleeding
    • Vitamin K Vitamin K A lipid cofactor that is required for normal blood clotting. Several forms of vitamin K have been identified: vitamin K 1 (phytomenadione) derived from plants, vitamin K 2 (menaquinone) from bacteria, and synthetic naphthoquinone provitamins, vitamin K 3 (menadione). Vitamin k 3 provitamins, after being alkylated in vivo, exhibit the antifibrinolytic activity of vitamin k. Green leafy vegetables, liver, cheese, butter, and egg yolk are good sources of vitamin k. Fat-soluble Vitamins and their Deficiencies, 4-factor prothrombin Prothrombin A plasma protein that is the inactive precursor of thrombin. It is converted to thrombin by a prothrombin activator complex consisting of factor Xa, factor V, phospholipid, and calcium ions. Hemostasis complex concentrate (4f-PCC), fresh frozen plasma Fresh Frozen Plasma Transfusion Products are options for warfarin Warfarin An anticoagulant that acts by inhibiting the synthesis of vitamin K-dependent coagulation factors. Warfarin is indicated for the prophylaxis and/or treatment of venous thrombosis and its extension, pulmonary embolism, and atrial fibrillation with embolization. It is also used as an adjunct in the prophylaxis of systemic embolism after myocardial infarction. Warfarin is also used as a rodenticide. Anticoagulants reversal.

Additional AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation treatment options

Catheter ablation:^{[1,3,14,15,21,25]}

• Nonpharmacologic rhythm control
• Minimally invasive procedure involving cryoablation Cryoablation Fibroadenoma ( cryotherapy Cryotherapy A form of therapy consisting in the local or general use of cold. The selective destruction of tissue by extreme cold or freezing is cryosurgery. Chondrosarcoma) or radiofrequency ablation Radiofrequency ablation Removal of tissue using heat generated from electrodes delivering an alternating electrical current in the frequency of radio waves. Hepatocellular Carcinoma (HCC) and Liver Metastases (RFA)
• Aims to stop abnormal electrical signals in the atrial tissue ( pulmonary veins Pulmonary veins The veins that return the oxygenated blood from the lungs to the left atrium of the heart. Lungs: Anatomy)
• Indications:
  • Severe symptomatic AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation is drug-refractory or medication is not tolerated. 
  • Reasonable option for symptomatic AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation and heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR) with reduced ejection fraction Ejection fraction Cardiac Cycle (↓ mortality Mortality All deaths reported in a given population. Measures of Health Status and hospitalizations)

Left atrial appendage (LAA) obliteration:^[1,3,14,15]

• For stroke prevention
• An option for those who have contraindications Contraindications A condition or factor associated with a recipient that makes the use of a drug, procedure, or physical agent improper or inadvisable. Contraindications may be absolute (life threatening) or relative (higher risk of complications in which benefits may outweigh risks). Noninvasive Ventilation to anticoagulation Anticoagulation Pulmonary Hypertension Drugs
  • Most thromboemboli come from the LAA, so occlusion or ligation Ligation Application of a ligature to tie a vessel or strangulate a part. Esophageal Atresia and Tracheoesophageal Fistula of the LAA can reduce stroke risk in AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation.
  • About 10% of thrombi are not from the LAA, so the risk of stroke is not completely eliminated.
• Options:
  • Percutaneous (with the Watchman device)
  • Surgical

Underlying conditions and risk-factor modifications^[1,3,15]

• Treatment of underlying conditions (e.g., infection, electrolyte abnormalities, ischemia Ischemia A hypoperfusion of the blood through an organ or tissue caused by a pathologic constriction or obstruction of its blood vessels, or an absence of blood circulation. Ischemic Cell Damage) is recommended.
• Weight loss Weight loss Decrease in existing body weight. Bariatric Surgery and exercise in obese or overweight individuals with AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation have beneficial effects and are recommended.

Management checklist

• Detection of atrial fibrillation Atrial fibrillation Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation
• Initial management → determine hemodynamic stability:
  • Hemodynamically unstable (↓ BP, heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR) due to rapid VR) → emergent cardioversion Cardioversion Atrial Fibrillation
  • Hemodynamically stable:
    • Rate control ( beta-blockers Beta-blockers Drugs that bind to but do not activate beta-adrenergic receptors thereby blocking the actions of beta-adrenergic agonists. Adrenergic beta-antagonists are used for treatment of hypertension, cardiac arrhythmias, angina pectoris, glaucoma, migraine headaches, and anxiety. Class 2 Antiarrhythmic Drugs (Beta Blockers) or CCB)
    • Evaluate for valvular/structural heart disease
    • Determine other precipitating factors and treat accordingly
    • Assess AC indications to prevent thromboembolism Thromboembolism Obstruction of a blood vessel (embolism) by a blood clot (thrombus) in the blood stream. Systemic Lupus Erythematosus 
• Subsequent management:
  • Evaluate rhythm versus rate control with the following considerations:
    • Age
    • Symptoms
    • CV CV Vasculitides risk
    • AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation duration
    • Other individual factors
• Rhythm control:
  • AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation < 48 hours and low stroke risk → cardioversion Cardioversion Atrial Fibrillation (AC before procedure in high stroke risk)
  • AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation > 48 hours and/or high stroke risk (must have no contraindications Contraindications A condition or factor associated with a recipient that makes the use of a drug, procedure, or physical agent improper or inadvisable. Contraindications may be absolute (life threatening) or relative (higher risk of complications in which benefits may outweigh risks). Noninvasive Ventilation to anticoagulation Anticoagulation Pulmonary Hypertension Drugs):
    • Anticoagulate for 3 weeks and return for cardioversion Cardioversion Atrial Fibrillation
    • Anticoagulate for shorter period, TEE TEE Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues using a transducer placed in the esophagus. Imaging of the Heart and Great Vessels to rule out thrombus and proceed with cardioversion Cardioversion Atrial Fibrillation if with no thrombus found
  • After cardioversion Cardioversion Atrial Fibrillation, long-term AC is determined by thromboembolic and bleeding risk.
• Rate control:
  • Beta-blockers Beta-blockers Drugs that bind to but do not activate beta-adrenergic receptors thereby blocking the actions of beta-adrenergic agonists. Adrenergic beta-antagonists are used for treatment of hypertension, cardiac arrhythmias, angina pectoris, glaucoma, migraine headaches, and anxiety. Class 2 Antiarrhythmic Drugs (Beta Blockers) or CCB (1st line)
  • Long-term AC is determined by thromboembolic risk (CHA₂DS₂-VASc score) and bleeding risk (HAS-BLED score)

Differential Diagnosis

The following conditions are differential diagnoses for AF AF Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation:

• Atrial flutter Atrial flutter Atrial flutter is a regular supraventricular tachycardia characterized by an atrial heart rate between 240/min and 340/min (typically 300/min), atrioventricular (AV) node conduction block, and a “sawtooth” pattern on an electrocardiogram (ECG). Atrial Flutter: an irregular heart rhythm of the atria. It is classified as supraventricular tachycardia Tachycardia Abnormally rapid heartbeat, usually with a heart rate above 100 beats per minute for adults. Tachycardia accompanied by disturbance in the cardiac depolarization (cardiac arrhythmia) is called tachyarrhythmia. Sepsis in Children. Symptoms include palpitations Palpitations Ebstein’s Anomaly. Complications include increased risk of stroke and heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR).
  • Key difference: Flutter is a regular Regular Insulin rhythm whereas fibrillation is irregular. 
• Paroxysmal supraventricular tachycardia Tachycardia Abnormally rapid heartbeat, usually with a heart rate above 100 beats per minute for adults. Tachycardia accompanied by disturbance in the cardiac depolarization (cardiac arrhythmia) is called tachyarrhythmia. Sepsis in Children: a type of supraventricular tachycardia Tachycardia Abnormally rapid heartbeat, usually with a heart rate above 100 beats per minute for adults. Tachycardia accompanied by disturbance in the cardiac depolarization (cardiac arrhythmia) is called tachyarrhythmia. Sepsis in Children characterized by narrow QRS complexes and a fast heart rhythm, typically between 150 and 240 beats per minute
• Multifocal atrial tachycardia Multifocal atrial tachycardia Tachyarrhythmias: a type of atrial arrhythmia characterized by rapid heart rate Heart rate The number of times the heart ventricles contract per unit of time, usually per minute. Cardiac Physiology with at least 3 or more P wave P wave Electrocardiogram (ECG) morphologies. It is called multifocal Multifocal Retinoblastoma since the signals arise from various zones within the atria other than the sinus node. 
• Premature Premature Childbirth before 37 weeks of pregnancy (259 days from the first day of the mother’s last menstrual period, or 245 days after fertilization). Necrotizing Enterocolitis atrial contractions: common ectopic beats generated from foci in atria, triggering premature Premature Childbirth before 37 weeks of pregnancy (259 days from the first day of the mother’s last menstrual period, or 245 days after fertilization). Necrotizing Enterocolitis heartbeats