Background: A review was conducted of published clinical trials of adjuvant
medical therapy in infrainguinal bypass procedures to evaluate the strengt
h 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 random
ized and double-blind design. Most were single-centre studies including a m
ixture of different surgical procedures and patients with varying degrees o
f lower limb ischaemia. Clinical outcomes were seldom reported. The median
sample size was 61. The median follow-up duration was 12 months, but was of
ten not standardized for all patients in a trial. Only aspirin in prostheti
c grafts and ticlopidine in vein grafts have been shown in well designed, d
ouble-blind, randomized, controlled trials to reduce the likelihood of occl
usion in infrainguinal bypass grafts.
Conclusion: The majority of the trials reviewed had significant deficiencie
s in their design, reducing the reliance that can be placed on their result
s. Further studies are required to investigate adequately the effectiveness
of existing medical therapies for the maintenance of infrainguinal bypass
grafts.