Assessment of left ventricular function from the mitral valve echocardiogram following positive and negative inotropic interventions.

The echocardiographically visualized mitral valve motion pattern has been shown to be related to left ventricular diastolic parameters and systolic performance. In order to analyze the influence of a negative inotropic agent (penbutolol, Betapressin) and a positive inotropic drug (AR-L 115 BS, Vardax) on the movement of the anterior mitral valve leaflet (aMV), the following motion phases of the aMV were determined in 23 patients following completion of diagnostic cardiac catheterization: DE slope, EF slope, the final closing velocity of the aMV (AC/BC slope), CE amplitude, AC interval, and PQ-AC interval. These values were compared to several hemodynamic parameters. In 13 patients (group I) control values were obtained under physiological conditions as well as during right atrial pacing at constant pacing rate in order to exclude changes in heart rate. Measurements were repeated under spontaneous heart rate and during atrial pacing following the application of penbutolol. In the other 10 patients (group II) the echocardiographic and hemodynamic data were obtained before and after the intravenous application of AR-L 115 BS. In addition, left ventriculography was repeated in 8 patients after the pharmacologic intervention. The investigations revealed changes in the mitral valve motion pattern following negative and positive inotropic interventions. The most marked changes occurred in the AC/BC slope, which declined significantly after beta blockade with penbutolol (means 300.1 mm/s vs. means 208.4 mm/s; p less than 0.01). This effect proved to be unaffected by heart rate: there was also a reduction of the closure slope after application of penbutolol during atrial pacing (means 343.1 mm/s vs. means 268.6 mm/s; p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)