Diagnosis and Tests for Heart Attack

If a heart attack is suspected, call 112 or 102. Doctors begin tests within minutes of arrival.

Diagnosis combines symptoms, an ECG and blood tests, with imaging as needed. Treatment often starts before every test is back.

Electrocardiogram (ECG)

Done within minutes. It shows whether a main artery is blocked (ST elevation) and helps decide the urgent treatment. It may need repeating if the first is normal.

Blood tests

• Troponin: a protein released when heart muscle is damaged. It is the key test and is often repeated after a few hours.
• Blood count, kidney function, electrolytes, blood sugar and cholesterol.

Imaging

• Echocardiogram: shows how well the heart pumps and whether any wall moves poorly.
• Chest X-ray: checks the lungs and the size of the heart.
• Coronary angiography: a dye test through a thin tube from the wrist or groin that shows the blocked artery and allows angioplasty at the same time.
• CT coronary angiography, cardiac MRI and nuclear scans: used in selected cases.

Tests after a heart attack

Stress tests, repeat echocardiogram and rhythm monitoring may follow to guide treatment and recovery.

Other conditions that can look similar

Pulmonary embolism, aortic dissection, pericarditis, pneumonia, gastro-oesophageal reflux and muscle pain can mimic a heart attack. This is why tests matter.