Low-molecular-weight heparin for prevention of restenosis after femoropopliteal percutaneous transluminal angioplasty: a randomized controlled trial.

BACKGROUND Restenosis after angioplasty is essentially due to intimal hyperplasia. Low-molecular-weight heparins (LMWHs) have experimentally been shown to have antiproliferative effects in addition to their antithrombotic properties. Their potential in reducing restenosis remains to be established. Therefore, we wanted to test the hypothesis that LMWH plus aspirin is more effective than aspirin alone in reducing the incidence of restenosis/reocclusion in patients undergoing percutaneous transluminal angioplasty (PTA) of femoropopliteal arteries. Further, different effects of LMWH in patients treated for critical limb ischemia (CLI) or claudication only should be investigated. METHODS After successful PTA, 275 patients with symptomatic peripheral arterial disease (claudication or critical limb ischemia) and femoropopliteal obstructions were randomized to receive either 2500 IU of dalteparin subcutaneously for 3 months plus 100 mg of aspirin daily (n = 137), or 100 mg aspirin daily alone (n = 138). The primary end point was restenosis or reocclusion documented by duplex ultrasonography imaging at 12 months. RESULTS Restenosis/reocclusion occurred in 58 patients (44%) in the dalteparin group and in 62 patients (50%) in the control group (P = .30). In a subgroup analysis according to the severity of peripheral arterial disease, we found that in patients treated for claudication, restenosis/reocclusion developed in 43 (43%) in the dalteparin group, and in 35 (41%) in the control group (P = .70); in patients treated for CLI, restenosis/reocclusion was significantly lower in the dalteparin group (15, 45%) than in the control group (27, 72%; P = .01). No major bleeding events occurred in either group. CONCLUSIONS Treatment with 2500 IU dalteparin subcutaneously given for 3 months after femoropopliteal PTA failed to reduce restenosis/reocclusion at 12 months. However, dalteparin may be beneficial in the subgroup of patients with CLI at 12 months follow-up.