Diagnostic tests for heart attack
If you have the symptoms of a heart attack, tests can help doctors find out with certainty if and where your heart's blood flow is blocked. Armed with this information, doctors can start lifesaving treatment.
Electrocardiogram. Also known as an EKG or ECG, this painless test is done with electrodes attached to your legs, arms and trunk. The electrodes record electrical activity in the heart and reveal rhythm abnormalities that can be caused by damaged heart tissue.
Echocardiography. This test uses ultrasound to create an image of the size, shape and motion of the heart. This helps a doctor locate and assess damage caused by heart attack.
A device called a transducer, pressed against the chest, sends ultrasound waves toward the heart. The waves bounce off heart tissues and return to the transducer, which sends the data to a computer. The computer uses the information to create an image of the heart.
Blood tests. Injured heart muscle cells release proteins and enzymes into the bloodstream. Blood tests measure the amounts of these proteins and enzymes. Higher than normal levels are evidence of a heart attack.
Coronary angiography. This test gives a doctor an accurate map of coronary arteries—complete with any blockages.
A hollow, flexible tube or catheter is inserted through an artery in the arm or thigh. While watching a televised x-ray image, the doctor advances the catheter tip toward the heart. Dye is then injected. Heart and blood vessels are filmed while the heart pumps. The resulting picture, called an angiogram or arteriogram, reveals plaque, blockages or blood clots in coronary arteries.
The catheter tip can also be used to collect blood samples and measure pressure and blood flow inside the heart.