21 Clinical Notes

• Pericarditis refers to infection or inflammation of the pericardium surrounding the heart. The most frequent cause is a viral infection. Bacterial pericarditis can be a complication of tuberculosis. Other possible causes include cancer, which can invade the pericardium, and kidney failure which causes uremic pericarditis. Percarditis can also be due to severe chest trauma, with bleeding into the pericardial sac.
• Myocarditis is an inflammation of the myocardium. Myocarditis is commonly caused by a viral infection and can affect young, healthy peope. Myocarditis can also result from autoimmune disease, environmental toxins, alcohol, certain medications, and chemotherapy agents and radiation frequently used in breast cancer therapy. If enough cardiac muscle cells are damaged, chronic cardiomyopathy with impaired pumping power can result. Blood clots may form in the heart, possibly leading to heart attack or stroke. Chronic cardiomypathy may require a heart transplant.
• Endocarditis indicates inflammation of endocardium. Endocarditis is usually result of bacterial infection, may also be result of fungal infection. Hearts with cardiac birth defects or damaged or abnormal valves are particularly susceptible to endocarditis. Endocarditis begins when bacteria enter the bloodstream and settle on the endocardium. This can happen following dental surgery or in the hospital following placement of a central venous access line. Another common cause is unsterile self injection of drugs. Endocarditis can destroy heart valves, requiring their surgical replacement.
• A heart murmur is a soft sound made by turbulent blood flow in or near the heart during a heartbeat. Most murmurs are "innocent," meaning they have no clinical significance. Pregnant women often develop innocent murmurs because their blood volume and cardiac output increase while their cardiac valves remain the same size. Congenital cardiac defects, including atrial septal and ventricular septal defects (holes in the interatrial septum and interventricular septum), cause blood to flow in the wrong direction through the septum during systole, generating a murmur.
• Stenotic valves (valves that do not open all the way) or incompetent valvular heart disease, such as valvular stenosis and valvular insufficiency, occur when the valves do not function properly. Valvular stenosis is a narrowing of the valve opening that reduces the amount of blood flow. Valvular insufficiency is a regurgitation of blood that results from incomplete valve closure
• Coronary Artery Disease (CAD) is the leading cause of death for men and women in the United States. It occurs when cardiac arteries become hardened and narrowed due to the buildup of cholesterol, calcium, and plaque. This narrowing of coronary arteries, termed atherosclerosis, decreases blood supply to the heart muscle and leads to cardiac ischemia. Cardiac ischemia often causes heart pain known as angina, which is usually manifested as a crushing, smothering chest discomfort that may radiate to the back, neck, jaw, left arm.
• If a blood clot forms at the site of a plaque and suddenly blocks the artery completely, a myocardial infarction (MI) or heart attack, can occur. The insufficient blood supply causes necrotic damage, called an infarct. The affected heart muscle then scars, which affects the heart's ability to contract properly. This impairs the cardiac conduction system and can lead to arrhythmias (heart beat irregularities) and heart failure.
• Treatment involves restoring blood flow using a thrombolytic (clot dissolver) or coronary angioplasty (surgical repair of blood vessel). Sometimes atherosclerosis develops so slowly that collateral circulation (alternative blood supply growing around a blockage) will develop and can save some cardiac muscle in the event of a sudden coronary thrombosis (stationary blood clot).
• Percutaneous (through a puncture) balloon angioplasty involves threading a catheter past an area of atherosclerosis, inflating a balloon to compress the plaque against the vessel wall, then inserting a metal stent or sleeve, to keep the area open. A surgical procedure in which damaged sections of coronary arteries are replaced with new venous graftings, known as a coronary artery bypass graft (CABG), can also be done. Such procedures typically use the great saphenous vein of the leg or the internal throacic artery of the chest wall for the graft.