A heart attack should be diagnosed and treated quickly. Initial diagnosis is usually based on:
- Signs and symptoms (as described above) that are often gathered by the emergency medical team.
- Electrocardiogram (ECG or EKG) is a simple non-invasive test that charts the heart's electrical impulses and reveals signs of a past or recent heart attack. This test uses small adhesive pads called electrodes that are placed on the arms, legs, and chest. These electrodes are connected to a machine that detects and prints out the heart's electrical impulses, giving a 10-second snapshot of what the heart is doing right at that moment.
- Blood tests can detect if high levels of proteins (biochemical including CK, CK-MF and troponin) exist in the bloodstream. This would suggest a heart attack.
Other tests may be performed if emergency treatment does not resolve the symptoms, or if emergency or preventive treatments must be planned. These tests may include:
- Coronary angiography (also called a cardiac catheterization) is a minimally invasive procedure that uses a catheter (a long, thin flexible tube) inserted into a blood vessel in the leg, arm, or neck to take pictures of the coronary artery opening. This test allows doctors to measure the width of the artery and rate of blood flow. Contrast dye is used to make it easier to see and evaluate the artery opening. Your doctor may go ahead and perform a procedure called an angioplasty, or stent, if a blockage is found during angiography.
- Echocardiogram is a non-invasive test using ultrasound (sound waves) and a device called a transducer — which is placed on the surface of the chest — to create a moving picture of the heart. It shows areas of the heart muscle or valves damaged by the heart attack.