Effects of antihypertensive treatment on ultrasound measures of myocardial fibrosis in hypertensive patients with left ventricular hypertrophy: results of a randomized trial comparing the angiotensin receptor antagonist, candesartan and the angiotensin-converting enzyme inhibitor, enalapril

OBJECTIVE: To compare the effects of the angiotensin II receptor antagonist candesartan with the angiotensin-converting enzyme inhibitor enalapril on myocardial fibrosis evaluated by echoreflectivity analysis. METHODS: Hypertensive patients (n = 196) with echocardigraphically documented left ventricular hypertrophy were randomized to candesartan 8-16 mg/day (n = 91) or enalapril 10-20 mg/day (n = 105) with possible addition of hydrochlorothiazide (12.5-25 mg/day) for 48 weeks. Echoreflectivity analysis was performed on ultrasound two-dimensional tracings of the midapex septum with a specifically designed and validated software. Colour histograms were obtained; the primary outcome variable was the treatment-related change in histogram width (broadband), previously shown to correlate with collagen volume on endomyocardial biopsy; changes in mean colour scale were secondary outcome variable. RESULTS: Echoreflectivity analysis was feasible in 84 patients (48 candesartan, 36 enalapril). Broadband decreased significantly in the candesartan (-8.0 colour levels) and in the enalapril group (-12.9 colour levels) with no significant difference between treatments (P = 0.409); no significant changes occurred in mean colour scale. Patients under monotherapy (n = 46) showed similar trends as the larger intention to treat cohort, without significant difference between treatments. CONCLUSION: In hypertensive patients with left ventricular hypertrophy, both candesartan and enalapril induce a moderate but statistically significant reduction in an echoreflectivity index of myocardial fibrosis.