Myocardial infarction, commonly known as a heart attack, occurs when blood flow to a part of the heart muscle is blocked, leading to damage or death of heart tissue. Immediate medical intervention, such as angioplasty or thrombolytic therapy, is vital to restore blood flow and minimize heart damage. The assessment of the Polygenic Risk Score for myocardial infarction is based on the examination of 89 gene polymorphisms.
Genetic testing for myocardial infarction is included along with 14 other diseases in the Genetic Screening for Cardiovascular and Respiratory Diseases, Polygenic Risk Score.
Causes and non-genetic risk factors
Acute temporary occlusion of one or more coronary arteries that supply blood and nutrients to the heart can lead to acute myocardial infarction due to insufficient oxygen supply (ischemia). Depending on the area affected, cardiac function will be more or less compromised. This arterial occlusion may have different origins.
- Most heart attacks are triggered by the rupture of cholesterol deposits or plaques in the walls of the arteries, which progressively narrow the diameter of the arteries, a condition known as atherosclerosis. During a heart attack, a plaque can rupture and spill cholesterol and other substances into the bloodstream, forming a clot at the rupture site that can block blood flow.
- This blockage of the coronary arteries can also be caused by an air bubble (embolism) that becomes trapped in a coronary artery.
- Another triggering cause is a spasm or contraction of the coronary arteries that closes off blood flow in part of the heart muscle. Smoking or substance abuse can cause a life-threatening spasm.
Family history of myocardial infarction, especially at early-risk ages (before 55 or 65 years of age for men and women, respectively), represents a relevant genetic factor for myocardial infarction. However, other factors contribute to the appearance of some of these causes:
- Age. Men older than 45 years of age and women than 55 years of age.
- Tobacco use and long-term exposure to passive smoking.
- High blood pressure can damage the coronary arteries. When accompanied by obesity, high cholesterol, or diabetes, a condition known as metabolic syndrome, the risk increases even more.
- High levels of total cholesterol, LDL, or triglycerides increase the risk of infarction, while high levels of HDL would reduce it.
- Obesity is related to high blood cholesterol, high triglycerides, high blood pressure, and diabetes.
- Having both type I and type II diabetes increases the risk of having a heart attack.
- An inactive lifestyle contributes to high blood cholesterol, obesity, and high blood pressure.
- Stress.
- The use of illegal stimulant drugs such as cocaine or amphetamines can cause coronary artery spasms.
Symptoms
Not all people who have heart attacks have the same symptoms or with the same severity; some even have no symptoms at all. In addition, although the heart attack may be sudden at times, it is often associated with warning signs and symptoms in the hours, days, or weeks prior. The following are the most common symptoms of myocardial infarction:
- Intense pressure, fullness, tightness, pain, or discomfort in the center of the chest lasting more than a few minutes, which may spread to the shoulders, neck, arms, or jaw.
- Chest pain that worsens or does not improve with rest may be accompanied by sweating, cold and clammy skin, pallor, shortness of breath, nausea or vomiting, dizziness or fainting, unexplained weakness or fatigue, and rapid or irregular pulse.
Although chest pain is the main sign, it can also be confused with other conditions such as indigestion, pleurisy, pneumonia, or heartburn.
Prevention
Reducing or limiting risk factors can delay the time of myocardial infarction and reduce the severity if it does occur:
- Quit smoking. Smoking damages and narrows blood vessels, increasing the risk of coronary heart disease. Avoid passive smoking.
- Eat a diet low in fat, cholesterol, salt, and sugars, including fruits, vegetables, fish, and omega-3 fatty acids.
- Lose weight, exercise regularly, and maintain an active lifestyle.
- Limit alcohol intake.
- Avoid stress.
- Periodically control and prevent high blood pressure, high cholesterol, and diabetes.
