Myocardial Infarction

2488 Words10 Pages
A heart attack, also known as a myocardial infarction, usually occurs when a blood clot forms inside a coronary artery at the site of an atherosclerotic plaque. The blood clot severely limits or completely cuts off blood flow to part of the heart. In a small percentage of cases, blood flow is cut off when the muscles in the artery wall contract suddenly, constricting the artery. This constriction, called vasospasm, can occur in an artery that is only slightly narrowed by atherosclerosis or even in a healthy artery. Regardless of the cause of a heart attack, the oxygen deprivation is so severe and prolonged that heart muscle cells begin to die for lack of oxygen. About 1.1 million people in the United States have a heart attack every year;…show more content…
Arteriolar vascular constriction, heart rate increases, and renal retention of sodium and water all help to regulate cardial output. Ventricular dilatation is commonly seen. A large amount of ventricular myocardium is lost, contractility may be greatly compromised, and cardiogenic shock may ensue. Right ventricular infarction may occur with occlusion of the right coronary artery. With infarct affect the posterior wall of the left ventricle and the posterior interventricular septum, they extend to the right ventricular wall in 15 to 30% of cases. The central venous pressure may be elevated markedly if acute right ventricular failure develops. Low right ventricular output causing shock often responds well to vigorous fluid therapy but poorly to vasodilators. Infusions raise both right and left ventricular filling pressures. The diagnosis of right ventricular infarction is difficult but may be established by right sided ECG leads and echocardiographic studies (Bullock, 1996).


The goal of medical management is to minimized myocardial damage, preserve myocardial function, and prevent complications. These goals are achieved by reperfusing the area by emergency use of Percutaneous Transluminal Coronary Angioplasty (PTCA) or thrombolytic medication. Minimizing myocardial damage is also accomplished by reducing myocardial oxygen demand and increasing oxygen supply with medications, oxygen administration, and bed rest.

More about Myocardial Infarction

Get Access