Adjuvant medical therapy in peripheral bypass surgery

Background: A review was conducted of published clinical trials of adjuvant medical therapy in infrainguinal bypass procedures to evaluate the strength of the evidence for the use of various agents. Methods: Trials were identified by literature search. The methods used were reviewed and the results with each agent tested were assessed taking into account the soundness of the study design. Results: Thirty-three studies were identified; fewer than half had a randomized and double-blind design. Most were single-centre studies including a mixture of different surgical procedures and patients with varying degrees of lower limb ischaemia. Clinical outcomes were seldom reported. The median sample size was 61. The median follow-up duration was 12 months, but was often not standardized for all patients in a trial. Only aspirin in prosthetic grafts and ticlopidine in vein grafts have been shown in well designed, double-blind, randomized, controlled trials to reduce the likelihood of occlusion in infrainguinal bypass grafts. Conclusion: The majority of the trials reviewed had significant deficiencies in their design, reducing the reliance that can be placed on their results. Further studies are required to investigate adequately the effectiveness of existing medical therapies for the maintenance of infrainguinal bypass grafts.