What is the most common cause of myocardial infarction?

The most common cause of myocardial infarction is coronary artery disease (CAD). CAD occurs when the coronary arteries, which supply blood to the heart muscle, become narrowed or blocked due to the buildup of cholesterol and other substances, forming plaques. This process is known as atherosclerosis.

When the blood flow to a portion of the heart muscle is significantly reduced or obstructed, it can lead to ischemia, which can cause damage to the heart tissue, ultimately resulting in a myocardial infarction, commonly referred to as a heart attack. The prevalence of CAD is largely attributed to risk factors such as high cholesterol levels, smoking, obesity, lack of physical activity, and genetic predisposition.

While conditions like diabetes, hypertension, and heart valve disease can contribute to cardiac issues and increase the risk of heart attacks, they are not as directly linked to the occurrence of myocardial infarction as coronary artery disease is. Diabetes and hypertension are considered significant risk factors for developing CAD, but they do not inherently cause a myocardial infarction; rather, they exacerbate existing risk factors associated with CAD. Heart valve disease primarily impacts blood flow dynamics and can lead to other complications, but it is not the primary cause of a myocardial infarction.