The effects of intravenous verapamil administration (0.1 mg/kg as a bolus followed by an infusion of 0.007 mg/kg/min) were studied using high-temporal-resolution radionuclide angiography in 27 patients with hypertension. Verapamil administration increased heart rate from 69 ± 11 to 75 ± 12 beats/min (p < 0.001) and decreased systolic, diastolic and mean blood pressures (BPs) from 155 ± 21/102 ± 12 mm Hg (mean 119 ± 14) to 142 ± 19/95 ± 12 mm Hg (mean 109 ± 13) (p < 0.001 for all). Ejection fraction decreased significantly (from 65 ± 10% to 60 ± 11%, p < 0.005); peak filling rate, however, increased significantly only in patients in whom it was subnormal in the basal study (from 2.2 ± 0.4 to 3.0 ± 0.6 end-diastolic counts/s, p < 0.001). These latter patients had significantly higher values of left ventricular (LV) mass index than patients with normal or increased peak filling rate (129 ± 22 vs 112 ± 22 g/m2, respectively, p < 0.05). The isovolumic relaxation period changes were inversely related to the baseline values (r = 0.83, p < 0.001). In the subgroup of patients in whom isovolumic relaxation period lengthened, time to end systole decreased (from 360 ± 31 to 329 ± 30 ms, p < 0.025) and time to onset of rapid filling increased (from 420 ± 31 to 451 ± 34 ms, p < 0.025), whereas these 2 intervals had opposite patterns in patients in whom isovolumic relaxation period decreased or did not change. The delay in end systole during verapamil administration in patients in whom isovolumic relaxation period increased is likely a consequence of improved LV synchrony, as the coefficient of variation computed on functional images of LV time to end systole decreased, but it did not change in the other subgroup (from 26 ± 5% to 20 ± 3% [p < 0.005] and from 24 ± 3% to 24 ± 4% [difference not significant]).
Effects of Intravenous Verapamil Administration on Left Ventricular Diastolic Function in Systemic Hypertension
PACE, Leonardo;
1987-01-01
Abstract
The effects of intravenous verapamil administration (0.1 mg/kg as a bolus followed by an infusion of 0.007 mg/kg/min) were studied using high-temporal-resolution radionuclide angiography in 27 patients with hypertension. Verapamil administration increased heart rate from 69 ± 11 to 75 ± 12 beats/min (p < 0.001) and decreased systolic, diastolic and mean blood pressures (BPs) from 155 ± 21/102 ± 12 mm Hg (mean 119 ± 14) to 142 ± 19/95 ± 12 mm Hg (mean 109 ± 13) (p < 0.001 for all). Ejection fraction decreased significantly (from 65 ± 10% to 60 ± 11%, p < 0.005); peak filling rate, however, increased significantly only in patients in whom it was subnormal in the basal study (from 2.2 ± 0.4 to 3.0 ± 0.6 end-diastolic counts/s, p < 0.001). These latter patients had significantly higher values of left ventricular (LV) mass index than patients with normal or increased peak filling rate (129 ± 22 vs 112 ± 22 g/m2, respectively, p < 0.05). The isovolumic relaxation period changes were inversely related to the baseline values (r = 0.83, p < 0.001). In the subgroup of patients in whom isovolumic relaxation period lengthened, time to end systole decreased (from 360 ± 31 to 329 ± 30 ms, p < 0.025) and time to onset of rapid filling increased (from 420 ± 31 to 451 ± 34 ms, p < 0.025), whereas these 2 intervals had opposite patterns in patients in whom isovolumic relaxation period decreased or did not change. The delay in end systole during verapamil administration in patients in whom isovolumic relaxation period increased is likely a consequence of improved LV synchrony, as the coefficient of variation computed on functional images of LV time to end systole decreased, but it did not change in the other subgroup (from 26 ± 5% to 20 ± 3% [p < 0.005] and from 24 ± 3% to 24 ± 4% [difference not significant]).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
