Diagnosing Heart Attacks
When cells in the heart die, they release enzymes into the blood. These enzymes are called markers or biomarkers. Measuring the amount of these markers in the blood can show how much damage was done to your heart. These tests are often repeated at intervals to check for changes. The specific blood tests used are:
- Troponin test. This test checks the troponin (a protein found in muscle tissue) levels in the blood. It is considered the most accurate blood test to determine if a heart attack has occurred and how much damage was done to the heart.
- CK or CK-MB test. These tests check for the amount of the different forms of creatine kinase (an enzyme present in muscle, brain, and other tissues) in the blood.
- Myoglobin test. This test checks for the presence of myoglobin in the blood. Myoglobin is released when the heart or other muscle is injured.
Nuclear Heart Scan
A nuclear heart scan uses radioactive tracers (technetium or thallium) to outline heart chambers and major blood vessels leading to and from the heart. A nuclear heart scan shows any damage to your heart muscle.
Cardiac Catheterization With Angiography
During a cardiac catheterization, a thin flexible tube (catheter) is passed through an artery in the groin or arm to reach the coronary arteries. This test allows your doctor to:
- Determine pressure and blood flow in the heart's chambers
- Collect blood samples from the heart
- Examine the arteries of the heart by x-ray.
An angiography may also be performed during a cardiac catheterization. During a coronary angiography, a dye that can be seen on x-ray images is injected through the catheter into the coronary arteries. Your doctor can see the flow of blood through the heart and see where there are blockages.