[Contractile reserve as a new parameter for determining the performance of the heart muscle using a noninvasive...

Chronic cardiac insufficiency is an illness with increasing epidemiological importance and mortality. Therefore different invasive and non-invasive investigation methods for early recording were developed. The left ventricular ejection fraction (LVEF) has played a special role in this direction. The determination of the contractile reserve by means of non-invasive measurement of blood pressure and flow through the aortic valve is a new and up to now widely unknown method for recording the capability and power reserve of the of myocardium. Since no comparative investigations are known from literature and results from a follow-up are not available yet, we tested whether, by means of contractile reserve, the discrimination of subjects with different cardiac power is possible or not. Forty-two men between 44 and 62 years of age belonging to three groups with different cardiac power (persistence trained, healthy subjects and patients with CHD) were examined non-invasively. The main result of the study is that it is possible to distinguish between the three groups significantly by means of the contractile reserve. The largest value (15.25 W +/- 3.46 W) was found in the "persistence trained" group, followed by the "healthy subjects" (10.85 W +/- 4.19 W). The smallest values were from the "patients" group (7.88 W +/- 2.95 W). The differences between the mean values of the CHD "patients" and the "persistence trained" were significant (p < 0.001). Similar comparisons of the groups of "healthy subjects" and "trained persons" and "healthy subjects" and "patients", respectively, yield p values of p = 0.007 and p = 0.040. These differences are also significant. This study is a first investigation and description of the method. A validation only can be achieved by follow-up investigations.