[New, non-invasive index for recognition of the early stages of cardiac insufficiency].

Proceeding from the highly significant correlation of the pre-ejection period (PEP) with usual measures of contractility a new non-invasive index is given which allows to recognize a decrease in left ventricular contractile adaptability and, therefore, to diagnose early stages of heart failure. The so-called pre-ejection index is based on measuring the pre-ejection period in upright and supine posture under resting conditions. By means of series of measurements with 30 normal subjects and 30 patients with latent heart insufficiency is demonstrated that a highly significant separation of the two groups is possible. A newly developed so-called thermistor pulse transducer is described which is essential for an easy application technique. Suggestions are presented for determination of the pre-ejection index by means of a single channel E.C.G. apparatus and for automatic digital data acquisition.