What is a heart attack (myocardial infarction)?
A heart attack, or myocardial infarction, occurs when one or more regions of the heart muscle experience a severe or prolonged lack of oxygen caused by blocked blood flow to the heart muscle.
The blockage is often a result of atherosclerosis – a buildup of plaque composed of fat deposits, cholesterol, and other substances. Plaque ruptures and eventually a blood clot forms. The actual cause of a heart attack is a blood clot that forms within the plaque-obstructed area.
If the blood and oxygen supply is cut off severely or for a long period of time, muscle cells of the heart suffer damage and die. The result is dysfunction of the muscle of the heart in the area affected by the lack of oxygen.
What are the risk factors for heart attack?
There are two types of risk factors for heart attack, including the following:
|Inherited (or genetic)||Acquired|
|Inherited or genetic risk factors are risk factors you are born with that cannot be changed, but can be improved with medical management and lifestyle changes.||Acquired risk factors are caused by activities that we choose to include in our lives that can be managed through lifestyle changes and clinical care.|
Treatment for a heart attack:
The goal of treatment for a heart attack is to relieve pain, preserve the heart muscle function, and prevent death.
Treatment in the emergency department may include:
- intravenous therapy – nitroglycerin, morphine
- continuous monitoring of the heart and vital signs
- oxygen therapy – to improve oxygenation to the damaged heart muscle
- pain medication – by decreasing pain, the workload of the heart decreases, thus, the oxygen demand of the heart decreases
- cardiac medication – such as beta-blockers or calcium channel blockers to promote blood flow to the heart, improve the blood supply, prevent arrhythmias, and decrease heart rate and blood pressure
- fibrinolytic therapy – intravenous infusion of a medication which dissolves the blood clot, thus, restoring blood flow
- antithrombin/antiplatelet therapy – used to prevent further blood clotting
- antihyperlipidemics – medications used to lower lipids (fats) in the blood, particularly Low Density Lipid (LDL) cholesterol. Statins are a group of antihyperlipidemic medications, and include simvastatin (Zocor®), atorvastatin (Lipitor®), and pravastatin (Pravachol®), among others. Bile acid sequestrants – colesevelam, cholestyramine and colestipol – and nicotinic acid (niacin) are two other types of medications that may be used to reduce cholesterol levels.