COMPARATIVE EFFICACY OF THE INTRAVENOUS ADMINISTRATION OF LINSIDOMINE, A DIRECT NITRIC-OXIDE DONOR, AND ISOSORBIDE DINITRATE IN SEVERE UNSTABLE ANGINA - A FRENCH MULTICENTER STUDY

Aims Although, linsidomine shares common properties with nitrovasodila tors, it releases nitric oxide directly without catalytic involvement by thiols. We conducted a prospective, randomized, multicentre, parall el group, single-blind study to compare the efficacy of intravenous ad ministration of linsidomine with that of isosorbide dinitrate in unsta ble angina. Methods and results Between November 1990 and July 1992, 5 68 patients with suspected unstable angina (class IIIB of the Braunwal d classification) received a continuous infusion of either linsidomine (1 mg.h(-1) on average) or isosorbide dinitrate (2.5 mg.h(-1) on aver age) for 72 h. All patients received concomitant aspirin and intraveno us heparin, 81% beta-blockers and 38% calcium antagonists. Holter moni toring was performed in all patients and analysed blindly. Only 25% of the patients had at least one episode of chest pain during the study (24.6% vs 25.8% in the linsidomine and isosorbide dinitrate groups, P= 0.74), of which 12% were associated with ECG changes. Holter criteria yielded similar results in both groups: 33% of patients presented epis odes of myocardial ischaemia (32.6% vs 33.9% in the linsidomine and is osorbide dinitrate groups, P=0.74), while 45% showed episodes of ventr icular arrhythmia (43.5% vs 46.5% in the linsidomine and isosorbide di nitrate groups, P=0.48). The incidence of serious clinical events at 7 2 h (death, myocardial infarction or myocardial revascularization) was 6.5% (5% vs 8% in the linsidomine and isosorbide dinitrate groups, P= 0.17). Conclusion Intravenous linsidomine is at least as efficacious a s isosorbide dinitrate in the stabilization of patients with severe un stable angina.