The importance of minor abnormalities in the resting electrocardiogram

Minor abnormalities of the ST segment and T wave are seen in about 1% of the resting electrocardiograms of the 'normal' population. Such changes are found more commonly in people of African descent and with increasing age. In young people they are often not present when the recording is repeated. In epidemiological studies minor ST segment and T wave (ST-T) electrocardiographic changes have been found to be associated with an increased risk of death. However, a sizeable minority of subjects with such abnormalities have symptoms suggesting ischaemic heart disease, and the presence of such symptoms is much more important as a risk predictor than are the electrocardiographic changes themselves. It is important that 'non-specific' ST-T wave changes should be accurately documented, perhaps using the Minnesota code. Aircrew found to have such changes should have an effort test, but if this is normal and if they are asymptomatic their licences need not be restricted.