Comparison of clinical outcome of fixed-dose subcutaneous low molecular weight heparin (tinzaparin) with conventional heparin in unstable angina: a pilot study.

Forty patients who were hospitalized for unstable angina were randomized to receive treatment with either regular heparin (Group I) in conventional dose as continuous infusion for 5 days or fixed-dose low molecular weight heparin (LMWH) (Group II), 3500 units subcutaneous twice daily for a period of 5 days. Both the groups were evenly matched with regard to age, sex presence of risk factors and adjunctive drug therapy. The clinical endpoints at the end of 5 day therapy were: recurrence of angina, occurrence of myocardial infarction and need for urgent revascularization. In Group I, 6 out of 20 patients had recurrence of angina, of whom 3 required urgent coronary angiography and revascularization. In Group II, 4 out of 20 patients had recurrence of angina, of whom one patient required urgent angiography and angioplasty. There were no bleeding complications in either of the groups. The recurrent anginal episodes in the conventional heparin group correlated with low aPTT values at the time of angina. Thus, this pilot study suggests that LMWH is equally effective in the treatment of unstable angina, the advantage of LMWH being the ease of administration and no need for monitoring aPTT levels during therapy.