Acute Myocardial Infarction

The Common Vein Copyright 2008

Definition 

 

Myocardial infarction is a circulatory disorder of the heart caused by acute coronary occlusion usually by thrombus or by a ruptured plaque that secondarily accumulates platelet thrombi, and results in necrosis and myocardial injury.  It is clinically characterized by presence of symptoms of acute myocardial ischemia (ischemic chest pain or chest pain equivalent as dyspnea, diaphoresis, lightheadedness, palpitations).

 

The diagnosis is confirmed by characteristic EKG changes and biochemical markers of myocardial necrosis as reflected by typical rise and fall of cardiac enzymes: troponin I or T, CK-MB and is classified as ST elevation (STEMI)or non ST elevation myocardial infarction (NSTEMI) based on the EKG

 

The pathological diagnosis of myocardial infarction requires evidence of myocyte cell death  (i.e. necrosis of the myocardium) as a consequence of prolonged ischemia.(Luepker)

 

Treatment depends on the type of infarction (STEMI vs NSTEMI, but attempts are usually made to lyse thrombus and open the vessels by angioplasty or stenting in a timely manner in order to salvage myocardium aat risk.

 

Not a great pic !! Choose new one

Acute Myocardial Infarction(b) Sudden Severe Pain Pressure Discomfort

c) Unrelieved by TNG and Rest

71197c08c.800 substernal chest pain burning esophagus heart cardiac esophagitis reflux retrosternal chest pain radiating to neck and left arm unrelieved by rest and sublingual nitroglycerine myocardial infarction time hours CTscan 3D Davidof art Courtesy Ashley Davidofff MD

 

 

References

 

  1. Luepker RV, Apple Fs et al: Case definitions for acute coronary disease in epidemiology and clinical research studies. Circulation 108:2543, 2003