Effect of Amlodipine on Left Ventricular Mass in the Amlodipine Cardiovascular Community Trial

Summary: As part of the Amlodipine Cardiovascular Community Trial (ACCT), which was a large multicenter study designed to assess the effects of the calcium channel blocker amlodipine besylate (Norvasc) as monotherapy for treatment of mild to moderate hypertension, we sought to determine the effects of amlodipine on regression of left ventricular (LV) hypertrophy (LVH). The study began with a 2-week placebo run-in period (baseline), before which antihypertensive drugs had been discontinued. Amlodipine was then administered at 5–10 mg/ day during a 4-week titration/efficacy period. Patients achieving a goal diastolic blood pressure (DBP) of ≤90 mm Hg or a decrease in DBP of ≥10 mm Hg entered a 12-week maintenance phase and had the option to continue long-term therapy thereafter. Echocardiograms were obtained in a subset of patients at the end of the baseline period. In patients with LVH at baseline, echocardiograms were repeated at the end of 16 weeks of therapy (week 18), and at 42 weeks in patients continuing long-term therapy. Thirty-seven percent of 124 hypertensive patients screened for LVH at baseline had LVH detected on echocardiograms. Blacks had a higher incidence of LVH (64%) as compared with whites (34%, p < 0.05). Patients with LVH were more likely to have a higher baseline systolic BP (SBP) and DBP. Their sitting SBP and DBP decreased significantly from a mean of 163/102 mm Hg at baseline to 139/86 mm Hg with amlodipine therapy at week 18 (p < 0.0001). Amlodipine treatment produced a mean decrease of 20-g/m2 in LV mass index (p < 0.05) after 16 weeks of treatment and a mean decrease of 43 g/m2 in LV mass at week 42 (p < 0.001) as compared with baseline. There were no differences in the degree of LV mass regression between men or women or between older or younger patients; there was a trend to-ward less regression in blacks (–7 × 15 g/m2) as compared with whites (– 22 × 9 g/m2) at week 18.