Long-term nifedipine unloading therapy in asymptomatic patients with chronic severe aortic regurgitation

Vasodilating agents acutely reduce regurgitant volume and improve left ventricular performance in aortic regurgitation, but more information is necessary about their long-term efficacy. To evaluate the effects of 12 months of therapy with nifedipine, a randomized, double-blind, placebo-controlled trial was performed in 72 asymptomatic patients with severe aortic regurgitation. At 12 months, patients receiving nifedipine had a significant reduction in left ventricular end-diastolic volume index (110 +/- 19 versus 136 +/- 22 ml/m2, p less than 0.01) and mass (115 +/- 19 versus 142 +/- 16 g/m2, p less than 0.01) measured by two-dimensional echocardiography. They also had a reduction in left ventricular mean wall stress (360 +/- 27 versus 479 +/- 36 kdyne/cm2, p less than 0.001) and an increase in ejection fraction (72 +/- 8% versus 60 +/- 6%, p less than 0.05). These data show that the long-term unloading action of nifedipine is able to reverse left ventricular dilation and hypertrophy and suggest that such therapy has the potential to delay the need for valve replacement in asymptomatic patients.