Background: Two second-generation calcium channel blockers, felodipine and amlodipine besylate, have been associated with similar high mortality rates in patients with ischemic heart failure (HF) but not in patients with nonischemic causes of HF. In patients with nonischemic HF, amlodipine might have a beneficial effect on survival. However, no difference in mortality rates was found between felodipine and placebo in a nonischemic HF group. Felodipine 10 mg/d was used in 1 large study, a dose considered high for nonischemic HF usually associated with normal blood pressure (BP).
Objective: The aim of this study was to compare the effects of 12-week, low-dose treatment with felodipine versus those of an angiotensin-converting enzyme inhibitor, fosinopril sodium, in patients with nonischemic HF and normal BP.
Methods: This double-blind, randomized, crossover trial was conducted at Taipei Medical University Hospital (Taipei, Taiwan). Patients aged ≥ 18 years with angiographically proved, nonischemic HF and normal BP who were being treated with an optimal regimen of digitalis and diuretics were enrolled. After a 2-week run-in period, patients were randomized to first receive 12 weeks of treatment with felodipine tablets (2.5 mg/d) or fosinopril tablets (7.5 mg/d) and, after a 2-week washout period, were crossed over to the opposite treatment. Efficacy analysis was performed before (baseline) and after treatment and included symptomatic assessment using a 7-grade clinical scale; 2-dimensional echocardiography (2-D echo); exercise tests; and neurohumoral data, including plasma renin activity, plasma aldosterone, and 24-hour urinary epinephrine (E) and norepinephrine (NE) measurements. The primary end point was death due to HF, and the secondary end point was hospital admission due to worsening HF. Compliance was measured using a pill count at the end of each treatment period.
Results: We enrolled 33 patients. One developed worsening HF during the run-in period and was admitted. A total of 32 patients entered the study (18 men, 14 women; mean [SD] age, 48.2 [6.3] years [range, 34-56 years]; mean [SD] systolic BP, 117.2 [9.8] mm Hg [range, 100-138 mm Hg]; mean [SD] diastolic BP, 59.4 [5.7] mm Hg [range, 50-72 mm Hg]). No hospital admission or cardiac death due to HF occurred during 12 weeks of treatment. Twenty-seven patients were included in the felodipine assessment, and 30 patients were included in the fosinopril assessment. Significant improvement in clinical score was noted in both treatment groups (both P < 0.01). The clinical scores did not differ significantly between the 2 treatments. No significant differences were found in 2-D echo parameters between treatments or within groups after treatment versus baseline. Significant improvement in exercise duration was noted with both study drugs after treatment versus baseline (both P < 0.01). No significant difference in exercise duration was found between the 2 treatments. Urinary E and NE were not significantly different between treatments or after treatment with either study drug compared with baseline.
Conclusion: The present findings suggest that, in Chinese patients with moderate to severe HF who have normal BP and insignificant coronary artery disease and were being treated with diuretics and digitalis, a 12-week, low-dose course of felodipine (2.5 mg/d) as a vasodilator was associated with as satisfactory an outcome as standard treatment with fosinopril (7.5 mg/d).
Keywords: calcium channel blocker; felodipine; heart failure.