[Left precordial ECG lead (V5) in patients with coronary artery disease (author's transl)].

In patients with and without coronary artery disease who were undergoing anaesthesia, the V5 precordial lead was recorded in addition to the limb leads. ST segment depression in the left precordial leads, especially V5, can be an indication of myocardial ischaemia, such as can arise during the stress of anaesthesia or operation. As a measure of myocardial oxygen usage, the rate-pressure product was calculated. No alterations of the ST segment were noted during general or regional anaesthesia in twenty patients free of coronary artery disease. In four out of ten patients with coronary insufficiency however, ST segment depression and pre-terminal T-wave negativity were recorded. This study shows that besides calculation of the rate-pressure product, a V5 lead recording is also a means of continuous monitoring for the occurrence of myocardial ischaemia.