Comparative effects of fenoldopam mesylate and nitroprusside on left ventricular performance in severe systemic hypertension.
To compare the effects of fenoldopam (n = 15), a selective dopamine-1 agonist, and nitroprusside (n = 14) on left ventricular (LV) function in severely hypertensive subjects (diastolic blood pressure (BP) greater than 120 mm Hg), both agents were infused to reduce diastolic BP by 40 mm Hg (or less than 110 mm Hg). Indexes of LV systolic and diastolic functions were obtained using gated radionuclide angiography before the initiation of treatment and after targeted BP was achieved. Both fenoldopam and nitroprusside effectively reduced systolic and diastolic BP to target levels. Changes in heart rate, peak filling rate and relative end-diastolic volume were similar with both agents. Baseline ejection fraction increased after infusion of both drugs. The magnitude of the increase in ejection fraction was far greater with fenoldopam than with nitroprusside (+22% vs +8%; p = 0.04), despite a lesser reduction in systolic BP (-12 vs -22%, p = 0.002). Furthermore, the reduction in relative end-systolic volume (-35 vs -20%; p = 0.04), and increase in the ratio of peak systolic pressure to relative end-systolic volume (+43 vs +6%; p = 0.007) were greater after fenoldopam than after nitroprusside. The greater increment in parameters of LV systolic function produced by fenoldopam than by nitroprusside suggests an effect on LV performance that is independent of afterload reduction.
Department of Medicine, University of Tennessee Center for the Health Sciences, Memphis.
B B
BB
Hackman
B
B
Griffin
M
M
Mills
K B
KB
Ramanathan
D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D000328:Adult; D000704:Analysis of Variance; D001794:Blood Pressure / Q000187:drug effects; D016009:Chi-Square Distribution; D005260:Female; D018818:Fenoldopam; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000000981:diagnostic imaging / Q000188:drug therapy*; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D009599:Nitroprusside / Q000494:pharmacology* / Q000627:therapeutic use; D015635:Radionuclide Ventriculography; D014665:Vasodilator Agents / Q000494:pharmacology* / Q000627:therapeutic use; D016277:Ventricular Function, Left / Q000187:drug effects*
D014665:Vasodilator Agents; D009599:Nitroprusside; D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine; D018818:Fenoldopam