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Myocardial infarction (MI)
- Risk factors for women
Acute myocardial infarction (AMI), commonly known as a heart attack, is the interruption of blood supply to part of the heart, causing some heart muscle cells to die. It is most commonly due to occlusion (blockage) of a coronary artery following the rupture of a vulnerable atherosclerotic plaque, which is an unstable collection of lipids (fatty acids) and white blood cells (especially macrophages) in the wall of an artery. The resulting ischemia (restriction in blood supply) and oxygen shortage, if left untreated for a sufficient period of time, can cause damage or death (infarction) of heart muscle tissue (myocardium).
(From: From Wikipedia, the free encyclopedia)
The most common symptom of a heart attack in both men and women is some type of pain, pressure or discomfort in the chest. But it's not always severe or even the most prominent symptom, particularly in women. Women are more likely than men to have signs and symptoms unrelated to chest pain, such as:
- Neck, shoulder, upper back or abdominal discomfort
- Shortness of breath
- Nausea or vomiting
- Lightheadedness or dizziness
- Unusual fatigue
These signs and symptoms are more subtle than the obvious crushing chest pain often associated with heart attacks. This may be because women tend to have blockages not only in their main arteries, but also in the smaller arteries that supply blood to the heart — a condition called small vessel heart disease.
Many women tend to show up in emergency rooms after much heart damage has already occurred, because their symptoms are not those typically associated with a heart attack.
Although the traditional risk factors for coronary artery disease — such as high cholesterol, high blood pressure and obesity — affect women and men, other factors may play a bigger role in the development of heart disease in women. For example:
- Metabolic syndrome — a combination of fat around your abdomen, high blood pressure, high blood sugar and high triglycerides — has a greater impact on women than on men.
- Mental stress and depression affect women's hearts more than men's.
- Smoking is a greater risk factor for heart disease in women than in men.
- Low levels of estrogen after menopause pose a significant risk factor for developing cardiovascular disease in the smaller blood vessels (small vessel heart disease).
A diagnosis of myocardial infarction can be made after evaluation of a patient's complaints, an examination and a variety of tests:
- Clinical history of angina lasting for more than 20 minutes
- Changes in serial EKGs:
EKG changes after a heart attack (from Myocardial Infarction)
With an infarction changes in the QRS-complex are seen. The dead muscle tissue is no longer "electrically active". The EKG lead above the necrotic tissue looks through a window of dead muscle tissue right into the heart cavity, causing a negative Q-wave.
While the vast majority of abnormal Q waves are due to myocardial infarction (MI), others can be caused by other cardiac illnesses such as hypertrophic cardiomyopathy (the result of long-standing high blood pressure) and may simulate anterior or inferior myocardial infarction.
- Rise and fall of serum cardiac blood tests such as CPK and troponin levels.
Other tests are sometimes performed to check heart and cardiac valve function as well as the coronary artery anatomy and location of blockages:
Treatment aims to salvage as much heart muscle as quickly as possible ("time is muscle"), preserve heart function and to prevent complications such as heart failure. Oxygen, aspirin, and nitroglycerin (NTG) are used routinely as an initial therapy, often first given in the ambulance.
If the EKG confirms changes suggestive of a heart attack, medication is injected that dissolves blood clots obstructing the coronary arteries, or a Percutaneous coronary intervention (PCI) may be performed in STEMI, but to be effective requires to be performed in a very limited time span.
NSTEMI and NSTE-ACS
If the ECG does not show typical changes, the term "non-ST segment elevation ACS" is applied. The patient may still have suffered a "non-ST elevation MI" (NSTEMI). The accepted management of unstable angina and acute coronary syndrome is treatment with medications alone.