In a surprising revelation, a new study published in British Medical Journal suggests, the electrocardiogram (ECG) test commonly administered to people with cramping chest pains caused by angina has limited value in predicting future heart problems.

According to the study researchers, 47% of all heart attacks, etc. occurred in people suspected of having angina, despite a normal ECG. This means that ECGs are only marginally better at predicting heart problems than routine assessments, including patient history and physical examinations.

Angina or chest pain, the outcome of poor blood flow to the heart, causing a lack of oxygen to the heart muscle, is the first and most common symptom of coronary artery disease. Patients suspected of having angina, commonly undergo a stress ECG test while resting, or while exercising on a treadmill or a stationary bike. Electrodes placed on the body, help the machine record the timing of electrical signals in various heart chambers. The size and shape of these electrical waves are then checked by doctors for any indication of heart disease.

Adam Timmis, Professor - Clinical Cardiology at Barts and London Queen Mary's School of Medicine and Dentistry in London and his colleagues carried out the out the study on over 8,000 people with suspected angina, but who had not previously been diagnosed with heart disease.

The study results confirms clinical assessment is the best way for a doctor to diagnose a patient, by talking through symptoms and medical history.