Coronary artery disease is a condition in which the arteries of a person's heart have plaque buildup, decreasing the passageway for blood and oxygen to flow to the heart. A person will suffer from a heart attack, or myocardial infarction, if a portion of the heart muscle is not supplied with oxygen.
Causes
If a piece of plaque breaks off the wall of a coronary, or heart, artery, it can cause a myocardial infarction. Blood platelets sticking to a crack or tear on the artery will also induce a myocardial infarction. Severe plaque buildup on the artery walls restricts blood flow and will cause a heart attack.
Symptoms
A person suffering from a myocardial infarction will have persistent chest pain which lasts longer than 3 to 5 minutes, according to the American Red Cross. The pain feels like severe indigestion, heavy pressure or extreme tightness around the chest, according to Mayoclinic.com. She may have discomfort in her chest, arm, stomach, back, shoulder, neck or jaw. She will have troubled or noisy breathing, she may be out of breath and she may breathe faster. The skin of a person suffering from a myocardial infarction appears pale, and she may also sweat or have nausea.
Effects
A myocardial infarction due to coronary artery disease blocks blood flow to a segment of a person's heart. If blood flow is not restored, the heart muscle cells of the affected segment die or become irreversibly damaged. The cells will no longer be able to assist the heart muscle in contracting, reducing the heart's ability to pump and circulate blood. A myocardial infarction can lead to a sudden cardiac arrest where the heart cannot beat properly. A sudden cardiac arrest means the heart's electrical system is not working and the heart is unable to pump blood to a person's brain or vital organs, according to Suddencardiacarrest.org.
Risk Factors
A myocardial infarction may be triggered with increased physical activity, such as when a sedentary person suddenly decides to run. The sudden onset of stress from emotional factors or from illness may induce a myocardial infarction as well.
Warning
If a person is obese, sedentary, a diabetic, has high blood pressure, smokes or has a family history of coronary artery disease or heart attacks, he must check with his doctor prior to beginning an exercise program. Exercise increases his heart's need for oxygen and imposes a greater demand on his heart to circulate blood. A person with coronary artery disease is likely to suffer from a myocardial infarction during an unsupervised exercise session.
References
- Medline Plus: Heart Attack
- "First Aid/CPR/AED for Schools and the Community"; American Red Cross; 2006
- Sudden Cardiac Arrest: Sudden Cardiac Arrest Facts
