what is acute myocardial infarction

Acute myocardial infarction (AMI), commonly known as a heart attack, is a medical emergency where blood flow to a part of the heart muscle suddenly decreases or stops, usually due to the blockage of a coronary artery. This blockage often results from the rupture of an atherosclerotic plaque or a blood clot that obstructs the artery. The lack of blood and oxygen causes tissue death (infarction) in the affected part of the heart muscle. The main symptom of AMI is intense chest pain or discomfort, which can radiate to the left shoulder, arm, jaw, neck, or back. Other symptoms may include shortness of breath, nausea, sweating, feeling faint, and fatigue. Women and older adults may have atypical symptoms such as jaw pain, arm pain, or feeling unusually tired. AMI is diagnosed through a combination of symptoms, changes in the heart's electrical activity seen on an electrocardiogram (ECG), blood tests for cardiac biomarkers like troponin, and imaging or angiography that shows arterial blockage. It is classified mainly into two types based on ECG findings: ST-elevation myocardial infarction (STEMI) and non-ST elevation myocardial infarction (NSTEMI). Immediate treatment is crucial to restore blood flow and minimize heart damage, including medications, angioplasty, or other interventions. Overall, AMI is caused by acute obstruction of one of the coronary arteries leading to ischemia and necrosis of the heart muscle, and is a leading cause of death worldwide.