Drugs to prevent the re-occurrence of narrowing of blood vessels in peripheral arterial disease after the damaged blood vessels have been widened surgically

Peripheral arterial disease of leg arteries can progressively cause leg pain on walking, pain at rest, ulcers and gangrene because of reduced blood flow. An inflatable balloon catheter inserted into the artery is used to widen and unblock the affected artery (termed angioplasty) yet reoccurrence of narrowing (restenosis/reocclusion) frequently occurs because of platelet clumping (aggregation) and activated blood clotting in the damaged blood vessel. This review of 14 randomized clinical trials set out to determine if any drug was more effective than another in preventing renarrowing of the artery. Aspirin (50 to 330 mg), with or without dipyridamol, reduced the incidence of reocclusion at six to 12 months when compared with no therapy or vitamin K antagonists. Three trials showed that higher doses of aspirin had no advantage on early occlusions (within one month) and were more likely to cause gastrointestinal side effects and peptic ulcer. In one study, low molecular weight heparin was more effective than heparin over six months, without causing increased bleeding. Few studies were available for potent new antiplatelet drugs (ticlopidine, abciximab). In one study in high risk patients abciximab given into the vein tended to improve early patency. Results of large randomized studies are required.