Abrupt withdrawal of verapamil in ischaemic heart disease. The Danish Study Group on Verapamil in Myocardial Infarction.

In order to examine the potential hazards of abrupt withdrawal of verapamil 120 mg t.i.d. after six months treatment, a double blind placebo controlled study was designed as part of the Danish multicenter trial of verapamil in acute myocardial infarction. All patients had had a myocardial infarction six months before withdrawal. At the time of withdrawal, 30% of the verapamil and 28% of the placebo treated patients were experiencing angina pectoris. At follow-up after two to three weeks 15% of 212 patients in the verapamil treated group and 9% of 260 patients in the placebo treated group reported worsening or reappearance of angina pectoris (P less than 0.05). One patient in the placebo group developed a myocardial infarction, and one patient in the verapamil group had episodes of supraventricular tachycardia after withdrawal. A 'withdrawal syndrome' was not found.