[Apropos of acute changes in left ventricular filling induced by antihypertensive treatment]

Abstract

The purpose of the study was to interpret the acute improvement in left ventricular (LV) filling induced by a new calcium channel blocker (SR 33 557) using Doppler echocardiography. Thirteen patients, 29 to 68 years old (mean 52) with mild to moderate hypertension were examined by Doppler echocardiography before and 4 hours after treatment (SR 33 557: 300 mg). The LV filling parameters, E, A, A/E, VTIM, VTIA, VTIA/VTIM, pressure half time (PHT) and isovolumic relaxation time (IRT) were measured. An index of left atrial pressure was obtained by measuring the mean pulmonary arterial pressure (PAP). The following hemodynamic parameters were also obtained: systolic blood pressure (SBP), heart rate (HR), PR interval (PR), stroke volume (SV) at aortic origin, total systemic resistances (TSR), pulse wave velocity (PWV) at thoracic descending aorta, LV end systolic stress (ESS), LV geometry (thickness/radius: th/r) and systolic function indices: mean VCF and contractility (mean VCF-ESS relationship). Following acute treatment, E and VTIM increased, A, VTIA and PHT did not change, and A/E, VTIA/VTIM ans IRT decreased, both significantly (p < 0.05). PAP did not change, HR, SBP, TSR, PWV, ESS decreased and PR increased both significantly (p < 0.05). LV geometry and systolic function did not change. No significant relationship was found between LV filling changes and changes in hemodynamic parameters. In conclusion, the acute increase in early LV filling induced by the calcium blocker treatment may be interpreted as the consequence of the improvement in LV relaxation in the absence of any change in left atrial pressure.(ABSTRACT TRUNCATED AT 250 WORDS)