Effectiveness of calcium antagonist drugs in patients with unstable angina and proven coronary artery disease.

Eighty-five patients admitted to our CCU for unstable angina (UA) with proven coronary artery disease, in whom i.v. therapy with nitroglycerin (N) and heparin (H) did not reduce both painful and painless episodes of myocardial ischaemia, were treated by i.v. administration of verapamil (V) and diltiazem (D) in order to assess the efficacy of calcium antagonists in reducing myocardial ischaemia. All patients were given i.v. N + H throughout the whole study period; none showed significant increase in serum CK MB concentration. V and D were assigned following a double-blind, cross-over, placebo-controlled design after a 48 h period of N + H therapy. Continuous Holter monitoring (CHM) was performed during the whole study period. V and D significantly reduced the total number of ischaemic episodes day-1 (N + H = 6.8 +/- 3.9; D = 2.1 +/- 2.3, P less than 0.001; V = 1.7 +/- 2.7, P less than 0.001), the number of silent episodes (SE) (N + H = 5.2 +/- 3; D = 1.4 +/- 1.4, P less than 0.001; V = 1.5 +/- 2.5, P less than 0.001) and the duration of SE (N + H: 428 min for all patients, D: 61 min, V: 112 min). In patients with UA and proven CAD in whom i.v. N and H are ineffective to control myocardial ischaemia, V and D given i.v. reduced both painful and painless ischaemic episodes and allow safe delay of coronary arteriography and myocardial revascularization without adjunctive risk. Continuous Holter monitoring is important to detect the total ischaemic burden.

RCT Entities:   Population Interventions Outcomes