The effect of deslanoside on the duration of the phases of ventricular systole in man

Autor: Sidney Cohen, Richard S. Bornstein, Arnold M. Weissler, Alan R. Kamen, Clyde D. Schoenfeld
Rok vydání: 1965
Předmět:
Zdroj: The American Journal of Cardiology. 15:153-161
ISSN: 0002-9149
DOI: 10.1016/0002-9149(65)90449-2
Popis: In the present investigation we studied the effect of deslanoside on the duration of the phases of left ventricular systole as derived indirectly from simultaneous tracings of the electrocardiogram, the heart sounds and the external carotid arterial tracing. The phases of systole measured included the interval between the beginning of electrical activity and the second heart sound (Q-S 2 ), the interval between the first and second heart sound S 1 -S 2 and the interval between beginning ejection and the trough of the incisura of the carotid pulse tracing (LVET). All data were expressed relative to the regression relationships between heart rate and each of the measured intervals. Deslanoside, administered intravenously (1.6 mg.), induced a decrease in the duration of each of the measured phases of left ventricular systole. The abbreviation in Q-S 2 and S 1 -S 2 exceeded that in LVET, lending evidence for a decrease in both the pre-ejection and ejection phases of the cardiac cycle. Studies on the temporal course of this action of deslanoside demonstrated the presence of an effect at 10 minutes, with progression to a maximum at one to two hours, after which the abbreviation in systole remained relatively constant for eight hours. Studies over the ensuing five days revealed a serial dissipation of the drug effect. The mean response in the duration of each of the phases of systole during the first eight hours following administration of deslanoside proved to be dose-dependent. A significant diurnal abbreviation in the duration of the phases of left ventricular systole was observed. This diurnal effect must be considered in all studies involving serial measurements of the duration of the phases of the cardiac cycle. The determination of the duration of the phases of left ventricular systole offers a useful means for assaying digitalis effects on the human ventricle.
Databáze: OpenAIRE