Adverse cardiovascular outcomes in relation to suboptimal antithrombotic therapy use in patients undergoing peripheral artery disease angioplasty: lost opportunities?

INTRODUCTION: Current guidelines recommend antithrombotic therapy with either aspirin or clopidogrel for all patients with peripheral arterial disease (PAD). Nevertheless, cardiovascular comorbidities and perceived bleeding risk complicate antithrombotic management of PAD patients. We studied the proportion of patients receiving optimal (guideline-recommended) antithrombotic therapy, and second, assessed the impact of suboptimal antithrombotic therapy use to long-term outcomes of PAD patients. METHODS: We performed a single centre retrospective analysis of patients with significant PAD, requiring percutaneous intervention. All patients coded as undergoing peripheral artery percutaneous transluminal angioplasty (PTA) between January 2007 and December 2011 were reviewed. Antithrombotic medication on discharge postprocedure was recorded. RESULTS: Across the study period, 473 patients were coded as having received a PTA, but yet only 336 (71%) had data available for review: 218 (35.2%) male, mean age 73 ± 11 years. Of the whole cohort, 236 (70.2%) were discharged on optimal (guideline-recommended) antithrombotic therapy, 30 (8.9%) were considered 'overtreated' and 70 (20.8%) were undertreated. On multivariate analysis, patients with heart failure were more likely to be undertreated (OR 2.38, 95% CI: 1.15-5.00, p = 0.02) while patient with coronary artery disease were more likely to be overtreated (OR 4.00, 95% CI: 1.61-10.00, p = 0.03). Undertreated patients had an increased risk for all-cause mortality [hazard ratio (HR) 2.96, 95% CI 1.81-4.82: p = 0.00001] and cardiovascular mortality (HR 3.16, 95% CI: 1.49-6.68, p = 0.003). CONCLUSION: In this single centre cohort of patients undergoing PTA, suboptimal antithrombotic therapy was not uncommon and had a major impact on long-term outcomes, resulting in increased all cause and cardiovascular mortality.