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Cardiac surgery is the surgical management of cardiac abnormalities and of the great vessels of the thorax. In general terms, surgical intervention of the heart is performed to directly restore adequate pump Pump ACES and RUSH: Resuscitation Ultrasound Protocols function, correct inherent structural issues, and reestablish proper blood supply via the coronary circulation Circulation The movement of the blood as it is pumped through the cardiovascular system. ABCDE Assessment. Common interventions treat ischemic and valvular heart disease as well as disorders of the great vessels.
Last updated: Jan 16, 2024
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The operator needs to be familiar with the anatomy of the heart Anatomy of the heart The heart is a 4-chambered muscular pump made primarily of cardiac muscle tissue. The heart is divided into 4 chambers: 2 upper chambers for receiving blood from the great vessels, known as the right and left atria, and 2 stronger lower chambers, known as the right and left ventricles, which pump blood throughout the body. Heart: Anatomy and surrounding structures, as well as vascular territories, to avoid damaging vessels and nerves and to achieve successful reperfusion of the tissues.
Prevent retrograde flow Retrograde flow Veins: Histology, their closure produces heart sounds Heart sounds Heart sounds are brief, transient sounds produced by valve opening and closure and by movement of blood in the heart. They are divided into systolic and diastolic sounds. In most cases, only the first (S1) and second (S2) heart sounds are heard. These are high-frequency sounds and arise from aortic and pulmonary valve closure (S1), as well as mitral and tricuspid valve closure (S2). Heart Sounds that can be heard on auscultation:
View of the valves of the heart from an atrial perspective:
Atria removed
Assessment of the coronary arteries Arteries Arteries are tubular collections of cells that transport oxygenated blood and nutrients from the heart to the tissues of the body. The blood passes through the arteries in order of decreasing luminal diameter, starting in the largest artery (the aorta) and ending in the small arterioles. Arteries are classified into 3 types: large elastic arteries, medium muscular arteries, and small arteries and arterioles. Arteries: Histology starts with a review of their origin on an axial Axial Computed Tomography (CT) cut.
Coronary circulation, anterior view
Image by Lecturio.Coronary circulation, posterior view
Image by Lecturio.Right-dominant pattern of coronary circulation
Image by Lecturio.Left-dominant pattern of coronary circulation
Image by Lecturio.Codominant pattern of coronary circulation
Image by Lecturio.Ramification of the left and right coronary arteries from the ascending aorta
Image by Lecturio.Layers of loose connective tissue Loose connective tissue Connective Tissue: Histology that envelop the heart, forming a potential space.
Pericardial cavity without the heart
Image by Lecturio.Transverse view of the thorax
Image by Lecturio.Pericardiocentesis is an invasive procedure that consists of inserting a needle into the pericardial space Pericardial Space Pericardial Effusion and Cardiac Tamponade to extract, for diagnostic or therapeutic reasons, fluid from the pericardial space Pericardial Space Pericardial Effusion and Cardiac Tamponade.
Diagnostic pericardiocentesis (obtaining pericardial fluid Pericardial fluid Watery fluid produced in the serous and visceral pericardium surrounding the surface of the heart. Heart: Anatomy for diagnosis):
Therapeutic pericardiocentesis:
Unless the individual is in 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 or has an imminently life-threatening condition, a pericardiocentesis should be performed under ultrasound guidance.
Needle pericardiocentesis:
To successfully reach the pericardial cavity, the needle has to be pointed at a 45-degree angle toward the left midscapula while maintaining negative pressure on the syringe.
A pericardial window is a surgical procedure done on the parietal Parietal One of a pair of irregularly shaped quadrilateral bones situated between the frontal bone and occipital bone, which together form the sides of the cranium. Skull: Anatomy pericardium Pericardium A conical fibroserous sac surrounding the heart and the roots of the great vessels (aorta; venae cavae; pulmonary artery). Pericardium consists of two sacs: the outer fibrous pericardium and the inner serous pericardium. The latter consists of an outer parietal layer facing the fibrous pericardium, and an inner visceral layer (epicardium) resting next to the heart, and a pericardial cavity between these two layers. Heart: Anatomy to provide access to the pericardial space Pericardial Space Pericardial Effusion and Cardiac Tamponade and to evacuate occupying fluid and break loculations. The main goal of this procedure is to restore effective ventricular filling Ventricular filling Cardiac Cycle and 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.
There are no absolute 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. Relative 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 include coagulopathy, thrombocytopenia Thrombocytopenia Thrombocytopenia occurs when the platelet count is < 150,000 per microliter. The normal range for platelets is usually 150,000-450,000/µL of whole blood. Thrombocytopenia can be a result of decreased production, increased destruction, or splenic sequestration of platelets. Patients are often asymptomatic until platelet counts are < 50,000/µL. Thrombocytopenia, and lack of operator experience.
Subxiphoid approach (preferred because of its greater simplicity):
Anterolateral approach:
Example of a pericardial window
Image: “The place of pericardial window” by Toth et al. License: CC BY 2.0Coronary artery Coronary Artery Truncus Arteriosus bypass graft Graft A piece of living tissue that is surgically transplanted Organ Transplantation (CABG) surgery is an invasive revascularization Revascularization Thromboangiitis Obliterans (Buerger’s Disease) procedure that consists of placing grafts between the arterial and coronary circulations in order to bypass obstructed segments of the coronary arteries Arteries Arteries are tubular collections of cells that transport oxygenated blood and nutrients from the heart to the tissues of the body. The blood passes through the arteries in order of decreasing luminal diameter, starting in the largest artery (the aorta) and ending in the small arterioles. Arteries are classified into 3 types: large elastic arteries, medium muscular arteries, and small arteries and arterioles. Arteries: Histology and supply the myocardium Myocardium The muscle tissue of the heart. It is composed of striated, involuntary muscle cells connected to form the contractile pump to generate blood flow. Heart: Anatomy with oxygenated blood.
A median sternotomy is performed during many cardiac operations to include a coronary artery bypass graft.
Image by Lecturio.Illustration showing the heart before and after coronary artery bypass graft (CABG) surgery:
Vein grafts are used to bypass coronary obstructions.
Cardiac catheterization is an invasive procedure that consists of inserting a catheter into the systemic arterial circulation Circulation The movement of the blood as it is pumped through the cardiovascular system. ABCDE Assessment and advancing it toward the heart to inject contrast dye. This procedure allows for diagnostic vascular imaging and potential therapeutic intervention.
This procedure may be interventional or diagnostic.
There are no absolute 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 cardiac catheterization. However, if the likelihood of complications is reasonably high, the surgeon may consider other methods. Individuals with renal impairment should be treated cautiously, as contrast media Contrast Media Substances used to allow enhanced visualization of tissues. Computed Tomography (CT) may be nephrotoxic.
In the OR:
Operative care:
Cardiac catheterization can be done through an arterial or venous access. A modified version of the Seldinger technique Seldinger Technique Central Venous Catheter is used for percutaneous catheter insertion.
Ventriculography, the injection of contrast to visualize a ventricle, allows for measurement of ejection fraction.
Image: “Left ventriculography during systole showing apical ballooning akinesis with basal hyperkinesis in a characteristic takotsubo ventricle” by Tara C. Gangadhar. License: CC BY 2.0Left heart catheter inserted through a femoral approach
Image: “Left Heart Catheter” by BruceBlaus. License: CC BY-SA 4.0, cropped by Lecturio.Formerly known as coronary angioplasty and stenting, PCI is an invasive, nonsurgical procedure that consists of introducing a catheter into the coronary arteries Arteries Arteries are tubular collections of cells that transport oxygenated blood and nutrients from the heart to the tissues of the body. The blood passes through the arteries in order of decreasing luminal diameter, starting in the largest artery (the aorta) and ending in the small arterioles. Arteries are classified into 3 types: large elastic arteries, medium muscular arteries, and small arteries and arterioles. Arteries: Histology and using a balloon and stent to relieve an occlusion within the vessel.
Absolute:
Relative:
Preparation for PCI is substantially similar to that for cardiac catheterization, however door-to-balloon time (D2B time) is an important factor to consider.
Antiplatelet therapy:
For anticoagulation Anticoagulation Pulmonary Hypertension Drugs, unfractionated heparin Unfractionated heparin A highly acidic mucopolysaccharide formed of equal parts of sulfated d-glucosamine and d-glucuronic acid with sulfaminic bridges. The molecular weight ranges from six to twenty thousand. Heparin occurs in and is obtained from liver, lung, mast cells, etc. , of vertebrates. Its function is unknown, but it is used to prevent blood clotting in vivo and vitro, in the form of many different salts. Anticoagulants may be used at the time of PCI.
Antibiotic prophylaxis Prophylaxis Cephalosporins is not indicated.
The coronary arteries Arteries Arteries are tubular collections of cells that transport oxygenated blood and nutrients from the heart to the tissues of the body. The blood passes through the arteries in order of decreasing luminal diameter, starting in the largest artery (the aorta) and ending in the small arterioles. Arteries are classified into 3 types: large elastic arteries, medium muscular arteries, and small arteries and arterioles. Arteries: Histology are reached via radial, axillary, or femoral approach. The radial artery Radial Artery The direct continuation of the brachial trunk, originating at the bifurcation of the brachial artery opposite the neck of the radius. Its branches may be divided into three groups corresponding to the three regions in which the vessel is situated, the forearm, wrist, and hand. Forearm: Anatomy is preferred because of the decreased risk of bleeding. Stents are preferred over balloon angioplasty alone because of the decreased risk of restenosis.
Angiography:
Angioplasty and stent placement:
Example of a coronary stent, an expandable tubular metallic device
Image: “Lekton Magic coronary stent” by Maryam Moravej and Diego Mantovani. License: CC BY 3.0Coronary angiography showing severe stenosis of the left anterior descending (LAD) artery
Image: “Coronary angiography showing a severe proximal LAD stenosis” by V. Parisi et al. License: CC BY 2.0