Coronary artery disease triggers most heart attacks. In coronary artery disease, one or more of the heart arteries are blocked. This is often because of cholesterol-containing deposits known as plaques. Plaques may narrow the arteries, decreasing blood flow to the heart. If a plaque breaks open, it may trigger a blood clot in the heart.
According to Mayo Clinic, a heart attack can be triggered by a whole or partial blockage of a heart artery. One method to classify heart attacks is whether an electrocardiogram shows certain changes that need emergency invasive treatment. Your doctor may apply ECG results to explain these types of heart attacks.
• An acute complete blockage of a medium or large heart artery often implies you have had an ST-elevation myocardial infarction.
• A partial blockage usually means you have had a non-ST elevation myocardial infarction. Nevertheless, some people with NSTEMI have a total blockage.
It’s important to know that not all heart attacks are triggered by blocked arteries. Other causes include:
• Coronary artery spasm. This is a critical squeezing of a blood vessel that is not blocked. The artery generally has cholesterol plaques or there is early hardening of the vessel as a result of smoking or other risk factors.
• Certain infections. COVID-19 and other viral infections might trigger damage to the heart muscle.
• Spontaneous coronary artery dissection. This life-threatening condition is triggered by a tear inside a heart artery.