Incidence of Peripheral Arterial Disease in Patients With Coronary Artery Disease Following Cardiac Catheterization: A Prospective Observational Study

Introduction: Peripheral arterial disease (PAD) is a common vascular condition affecting roughly 800,000 Canadians annually with up to 50% being asymptomatic. As such, PAD is underdiagnosed and undertreated, despite being an independent predictor of cardiovascular (CV) risk. Moreover, PAD is commonly seen in patients with coronary artery disease (CAD) due to their shared atherosclerotic pathophysiology. Our aim was to gain a better understanding of the incidence and symptomatology of PAD in patients with established CAD on coronary angiography. Methods: Prospective subjects with CAD demonstrated on coronary angiography were immediately screened for PAD at the Mazankowski Alberta Heart Institute Cardiac Catheterization Laboratory. Following consent, a bedside ankle-brachial-index (ABI) (Microlife WatchBP Office ABI) was performed and the Edinburgh Claudication Questionnaire (ECQ) (validated for PAD) was administered. PAD was defined as an ABI≤0.90. Results: We recruited 100 patients (67.5 age ± 9.5 years, 18.0% female) between June 2021 to April 2022. Eighteen subjects (18.0%) had PAD as demonstrated by an abnormal ABI. In those with diabetes (n=34), PAD was more frequent (26.5% vs. 14.1%, p=0.068). Kappa agreement between ECQ and ABI was 0.32. Conclusions: In a prospective cohort of angiographically confirmed CAD patients, one-quarter had ABI confirmed PAD (even more common in diabetics). The ECQ provided modest agreement with ABI suggesting many of these subjects are asymptomatic. ABI can be used as a simple non-invasive tool at the bedside following cardiac catheterization to screen for PAD which has implications on subsequent guideline-directed medical therapy.