Is It a Heart Attack?

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Q. Glen, How do I know if I am having a Heart Attack

A.If you go to the emergency room with symptoms like chest pain, you'll probably be given tests to rule out other problems that could be causing the pain.

Physicians or emergency room staff must first determine whether you are having a heart attack, an episode of angina, or something completely unrelated to the heart (see Diagnosing Heart Disease). The American College of Cardiology recommends that a diagnosis of heart attack be made when two of the following three criteria are met:

• compatible symptoms (see Common Symptoms of a Heart Attack )
• suggestive EKG abnormalities
• blood tests that reveal elevated levels of the blood chemicals creatine kinase-MB or troponin (see "Blood Tests" below).

Because heart attacks are sometimes hard to distinguish from other causes of chest pain, your physician may also order additional tests, such as echocardiography, nuclear scans, and cardiac catheterization, before making a diagnosis.

EKG Patterns
Emergency room staff often do an immediate EKG; sometimes this is even done in the ambulance during the ride to the hospital. The EKG helps, in many cases (but not all), to determine whether you are having a heart attack, and if so what type of heart attack.

One type is a full-thickness heart attack, also known as a transmural heart attack. When such heart attacks follow the rules, they produce an injury current that shows up on an EKG as an ST segment elevation (see Types of Heart Attacks ). Cardiologists call this kind of heart attack an ST-elevation myocardial infarction, or STEMI.

A partial-thickness heart attack, or non-ST-elevation myocardial infarction, produces different EKG changes — or at least, it should. Instead of becoming elevated, the ST segment is depressed, or lowered.

To complicate matters, angina often produces exactly the same changes as a partial-thickness (non-STEMI) heart attack, and it can sometimes mimic a full-thickness (STEMI) heart attack. More often, the EKG abnormalities that accompany a heart attack are atypical, subtle, or even absent. That’s why doctors always use blood tests to diagnose heart attacks.

Blood tests
When heart cells die, they release enzymes, the chemicals that trigger vital tissue functions. Some of these enzymes are specific to the heart and aren’t produced in any other tissue in large quantities. Doctors measure the blood levels of these enzymes at intervals over time.

Because dying heart cells release different enzymes at different rates, the blood tests can help pinpoint the time the heart attack occurred — information that is particularly useful when symptoms are vague. In addition, the more cells that die, the higher the blood levels of these different enzymes. Doctors can use this information to estimate the amount of heart tissue that has been destroyed.

If doctors suspect that you are having a heart attack, they usually test the blood, either for a specific form of the enzyme creatine kinase (known as creatine kinase-MB) or for two forms of a chemical called troponin (troponin-T and troponin-I). The level of creatine kinase-MB goes up when there has been damage to heart tissue. It rises within 6 hours of a heart attack, reaches peak levels at about 18 hours, and returns to normal within 2–3 days. Testing for this enzyme is useful for the many people who arrive at the hospital several hours after the onset of a heart attack. Abnormally high levels of troponins are also evidence of a heart attack because these proteins begin to rise within minutes to hours after a heart attack. Troponin levels usually increase sharply about 4–6 hours after heart muscle has been damaged, reach peak levels in 10–24 hours, and return to normal 10–14 days later.

Any personal health questions or problems mental or physical or before starting any diet or exercise program.Please consult your physician !

Wishing You Great Health!

Glen Edward Mitchell

Any questions? Ask Glen