The diagnostic value of the repolarization pattern in the electrocardiographic lead V6.

T wave inversion confined to the lateral leads presents one of the commonest dilemmas in the field of electrocardiogram (ECG) reporting. The differentiation between lateral ischaemia and left ventricular hypertrophy is generally based on the presence or absence of the accepted voltage criterion of hypertrophy, even though this is admitted to have a relatively low degree of sensitivity. In this study the repolarisation pattern in V6 has been analysed in a consecutive series of 100 patients showing T inversion of at least 1 mm in this lead, and correlated with the diagnosis. Patients on digoxin or similar drugs were excluded. Thirty-four patients were diagnosed as having hypertension or aortic valve disease or a combination of the two conditions: 31 as pure ischaemic heart disease; 24 as a combination of ischaemic and hypertensive or aortic valvular disease and 11 as having miscellaneous diseases. Two abnormalities of the T wave showed a significant association with aortic valve disease and hypertension; namely marked asymmetry and terminal positivity (overshoot). These features were sometimes seen in these diseases when the commonly acceptable voltage criterion of left ventricular hypertrophy was lacking.