Heart Attack

• Heart attack (also called Myocardial infarction or MI) is one of the dreaded complications of heart disease (coronary artery disease or CAD), resulting from an accumulation of cholesterol plaque inside the coronary arteries.

• Heart attack is a sudden event occurring in minutes as opposed to heart disease which is a chronic process, developing over several decades. Heart attack is an extremely serious condition, requiring immediate medical attention.¹

• A heart attack occurs when a plaque suddenly ruptures, causing a rapid accumulation of clotting factors at the rupture site.  This results in a sudden obstruction of blood flow in the coronary artery.  This sudden obstruction prevents any blood from reaching the heart muscle.  Without this vital supply of oxygen-rich blood, the heart muscle begins to die.  The longer the obstruction persists, the greater the amount of heart muscle that dies. (click for the heart attack video)

• Contrary to common belief, most heart attacks are caused not by an artery narrowing due to the buildup of hard, large plaques detectable on a coronary angiogram, but by a blood clot that forms after the rupture of a soft, inflamed, lipid-rich plaque, often quite small.

• Without immediate treatment, a heart attack can cause permanent damage to the heart muscle and chaotic, abnormal heart beating.  Both conditions can cause sudden cardiac deaths.

• Most heart attacks among Americans occur after the age of 65 and only 3% occur in people younger than 45 years of age. In the US 80% of heart attacks occurs in people less than 75 years of age, 14% in people 75-84 years old, and 6% in people ≥85 years old (see Heart Disease in the US).^{2, 3}

• In sharp contrast, heart attack is about 10 times more common among Indians younger than 40-45 years than Americans, with 30% of death occurring in people <40years of age (see Tsunami of Heart Disease).^{1, 4}

• Although severe chest pain is the classical symptom of a heart attack, up to one-fourth of it especially among people with diabetes, occurs without any chest pain. Such silent heart attacks are detected when an EKG is done for some unrelated reason.

Sources

1. Enas EA. How to Beat the Heart Disease Epidemic among South Asians: A Prevention and Management Guide for Asian Indians and their Doctors. Downers Grove: Advanced Heart Lipid Clinic  USA; 2011.

2. Forman DE, Chen AY, Wiviott SD, Wang TY, Magid DJ, Alexander KP. Comparison of outcomes in patients aged <75, 75 to 84, and >/= 85 years with ST-elevation myocardial infarction (from the ACTION Registry-GWTG). Am J Cardiol. Nov 15 2010;106(10):1382-1388.

3. American Heart Association. Heart and Stroke Statistical Update2010.

4. Enas EA, Mehta J. Malignant coronary artery disease in young Asian Indians: thoughts on pathogenesis, prevention, and therapy. Coronary Artery Disease in Asian Indians (CADI) Study. Clin Cardiol. Mar 1995;18(3):131-135.