Heart Attack - Diagnosis
The diagnosis of heart attack is based on symptoms, review of the history and test results.
Diagnosis of heart attack is done taking into account the patient's symptoms, reviewing the patient's medical and family history, and test results. Tests for diagnosing heart attack include:
- Electrocardiogram (EKG or ECG): A 12-lead EKG is done to detect the electrical activity of the heart and detect abnormalities. In addition, it also helps in monitoring the rate and regularity of heartbeat.
- Blood Tests: Blood tests are done to measure the cardiac enzymes, which are released by the dying heart muscle. Tests to detect these enzymes include the:
a. Troponin test,
b. CK-MB test (CK test)
c. Myoglobin test.
These tests are very useful especially when EKG is not diagnostic.
- Echo-cardiogram: This is an ultrasound examination of the heart that can be used during and after a heart attack to learn how the heart is pumping and to see which areas are not pumping normally. It can also detect if any structures of the heart have been injured during the heart attack.
- Cardiac catheterization: This may be used during the first hours of a heart attack if medications are not relieving the block or symptoms. A thin flexible tube (catheter) is passed through an artery in the groin or arm to reach the coronary arteries. It can be used to directly visualize the blocked artery and help your doctor determine which procedure is needed to treat the blockage.
- Coronary angiography: This is the best test for identifying blockages in the coronary arteries. This test is usually performed along with cardiac catheterization. A dye is injected through the catheter into the coronary arteries to make them stand out on x-rays.
- Stress test: A stress test may be performed after the patient is stable and recovering from the heart attack and/or procedure. The stress test involves recording an EKG while the heart is stressed and again at rest. This test helps in assessing the heart function after heart attack. The exercise stress test is about 60-70% accurate in predicting increased risk of future heart attacks. Common stress tests include Treadmill Stress test and Thallium stress test.
- Multislice Computed Tomography (MSCT) Angiogram: Multislice CT systems with 16 or more detectors have made a quantum leap into imaging of the coronary arteries. If EKG's, stress tests or other indicators have revealed a potential cardiac problem, multislice CT angiography provides a better diagnostic option to have a detailed 3D virtual model of the patient's heart. In less than 30 minutes, without the invasiveness of a Cardiac catheterization, a patient can have an MSCT done to determine if there are any arterial blockages that require an intervention. It is a less invasive and less expensive method of ruling out the need for additional intervention.