Myocardial ischemia develops when blood flow to the heart muscle is decreased by a partial or complete blockage of the heart’s arteries (coronary arteries). The decrease in blood flow reduces the oxygen supply of the heart.
Myocardial ischemia can damage the heart muscle impairing its ability to pump efficiently and may cause serious abnormal heart rhythms. A sudden, severe blockage of a coronary artery can lead to a heart attack.
Treatment for myocardial ischemia focuses on improving blood flow to the heart muscle through medications or procedures to open blocked arteries or coronary artery. A healthy lifestyle is also important in treating and preventing myocardial ischemia.
Symptoms of myocardial ischemia include:
- Chest pressure or pain, typically on the left side of the body (angina pectoris)
- Neck or jaw pain
- Shoulder or arm pain
- Fast heartbeat
- Shortness of breath
- Nausea and vomiting
In some cases, a myocardial ischemia may be asymptomatic, which is called silent ischemia.
Myocardial ischemia occurs due to a decrease in blood flow through one or more of the coronary arteries that lead to the heart. A decrease in blood flow decreases the amount of oxygen the heart muscle (myocardium) receives. Myocardial ischemia can occur gradually as the arteries become blocked over time or rapidly when an artery is blocked suddenly.
Conditions that may cause myocardial ischemia:
- Coronary artery disease (atherosclerosis)
- Blood clot
- Coronary artery spasm
Triggers of chest pain associated with myocardial ischemia include:
- Physical exertion
- Emotional stress
- Cold temperatures
- Lying down
- Cocaine use
Risk factors for myocardial ischemia include:
- Tobacco: Smoking can damage the interior walls of arteries allowing cholesterol deposits and other substances to slow blood flow. Smoking also increases the risk of blood clots in the arteries.
- Diabetes: Type 1 and type 2 diabetes may increase the risk of myocardial ischemia, heart attack or other heart problems.
- High blood pressure: Over time high blood pressure can damage the arteries by accelerating atherosclerosis. Obesity and a diet high in salt can also increase the risk of high blood pressure.
- High blood cholesterol or triglyceride levels: High levels of LDL cholesterol and triglycerides can narrow the arteries throughout the body and contribute to atherosclerosis and myocardial ischemia.
- Lack of physical activity: Lack of exercise contributes to obesity and high cholesterol and triglycerides, which increases the risk of atherosclerosis.
- Obesity: Obesity increases the risk of myocardial ischemia due to its relation to high blood cholesterol, high blood pressure and diabetes.
- Waist circumference: A waist circumference of more than 88cm in women and 102cm or more in men increases the risk of heart disease.
- Family history: Family history of heart attack or coronary artery disease can increase the risk of myocardial ischemia.
Complications of myocardial ischemia may include:
- Heart attack (myocardial infarction): Complete blockage of a coronary artery causes lack of blood and oxygen that leads to a heart attack that may result in serious or fatal heart damage.
- Irregular heart rhythm (arrhythmia): Without enough oxygen the electrical impulses that coordinate the heartbeats may malfunction causing arrhythmias that can be life-threatening in some cases.
- Heart failure: Myocardial ischemia can damage the heart leading to a decreased ability to effectively pump blood. Over time, the damage can result in heart failure.
A healthy lifestyle can prevent the development of myocardial ischemia.
Maintaining a healthy lifestyle includes:
- Quitting smoking and avoiding secondhand smoke or chewing tobacco
- Managing conditions such as high blood pressure, high cholesterol and diabetes
- A low-fat and low-salt diet
- Reducing and managing stress