Long-term effects of benidipine hydrochloride on severe left ventricular hypertrophy and collagen metabolism in patients with essential hypertension.

OBJECTIVES: The long-term effects of benidipine on left ventricular hypertrophy (LVH) and collagen metabolism were examined in patients with essential hypertension. METHODS: Forty patients with untreated essential hypertension were given benidipine at a dose of 6 mg a day. Routine echocardiographic parameters, serum concentrations of matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of metalloproteinase-1 (TIMP-1) were analyzed before and 12 months after treatment with benidipine. Patients were classified according to left ventricular mass index (LVMI) into three groups: severe LVH (LVMI > or = 159), mild LVH (159 > LVMI > or = 125) and no LVH (LVMI < 125). RESULTS: Serum levels of free TIMP-1 to MMP-1 ratio were significantly higher in patients with severe LVH than in the other two groups before treatment. There was a significant positive correlation between the free TIMP-1 to MMP-1 ratio and LVMI in all study subjects (r = 0.51, p < 0.01). Twelve months after treatment, percentage changes of the LVMI and free TIMP-1 to MMP-1 ratio were significantly larger in the patients with severe LVH (-27% and -54%) than with mild LVH (-12% and -23%) or no LVH (-4% and -11%), respectively. Changes in the systolic blood pressure but not changes in the free TIMP-1 to MMP-1 ratio correlated with changes in the LVMI in patients with mild LVH (r = 0.78, p < 0.01). Changes in the free TIMP-1 to MMP-1 ratio but not changes in the systolic blood pressure correlated with changes in the LVMI in patients with severe LVH (r = 0.69, p < 0.01). CONCLUSIONS: Long-term administration of benidipine reduced left ventricular mass and normalized systemic collagen type I degradation abnormalities in essential hypertensive patients with severe but not mild LVH.