A heart attack occurs when one or more of your coronary arteries becomes blocked. Over time, a buildup of fatty deposits, including cholesterol, form substances called plaques, which can narrow the arteries (atherosclerosis). This condition, called coronary artery disease, causes most heart attacks.

Which artery is the most common to have blockage?

Although blockages can occur in other arteries leading to the heart, the LAD artery is where most blockages occur. Niess said about one-third of coronary heart disease patients have blockages in one artery, about one-third have blockages in two arteries and one-third have blockages in all three arteries.

Is a heart attack always caused by a blockage?

Can You Have a Heart Attack Without Having Any Blocked Arteries? Yes, heart attacks are possible without having a blocked artery. Find out more about this type of heart attack, called a myocardial infarction in the absence of obstructive coronary artery disease (or MINOCA).