[Calcium antagonists and prevention of post-angioplasty restenosis]

Five randomised double blind clinical trials have assessed the effects of long term therapy with calcium antagonists on post-coronary angioplasty restenosis. Nifedipine 40 mg/day was tested in 241 patients by Whitworth et al: there was no difference in the incidence of restenosis between the treatment and placebo groups. Corcos et al studied the effects of diltiazem 270 mg/day in 92 patients: there was no significant difference between the two groups. In a study of 201 patients, O'Keefe et al found no significant difference in incidence of restenosis in a group treated with diltiazem (240 to 360 mg/day) compared with placebo. The fourth trial, conducted by Unverdorben et al, not yet fully published, in 170 patients, showed a significant reduction in restenosis in patients treated with diltiazem 180 mg/day (p = 0.03). Finally, the VAS trial (Verapamil Angioplasty Study) showed high dose verapamil (480 mg/day) to reduce the incidence of restenosis in a subgroup of patients with stable angina and high risk of restenosis.