Abstract 4142820: Vessel-by-Vessel CT Calcium Scoring in Peripheral Artery Disease: Association with Patient-Level Factors

Introduction: Peripheral artery disease (PAD) is an atherosclerotic condition that promotes lower extremity arterial calcification, which can decrease skeletal muscle perfusion, limit revascularization options, contribute to worse revascularization outcomes, and increase risk of adverse events. Although vascular calcium scoring via computed tomography (CT) imaging has already gained attention for risk assessment in coronary artery disease (CAD), analytical methods for vessel-by-vessel CT calcium scoring in PAD remain underdeveloped and understudied. We hypothesized that CT imaging would allow for vessel-specific calcium scoring in PAD patients and elucidate the contributions of patient-level factors promoting vascular calcification. Methods: PAD patients (n=90) were prospectively enrolled and underwent non-contrast CT imaging of the legs (CT parameters: slice thickness 3.27 mm, 120 kVp, 85 mA). Five arteries of interest (femoral-popliteal, anterior tibial, tibioperoneal trunk, posterior tibial, peroneal) were manually segmented using axial CT images along the length of the symptomatic limb. Calcium mass was quantified for each arterial segment using a CT image threshold of ≥130 Hounsfield units and mean calcium mass was calculated for each artery. T-tests were used to compare calcium values between patients with (n=62) and without diabetes mellitus (DM) (n=28). Multivariate linear regression was conducted to assess the role of patient-level factors on vessel-specific calcium burden. Results: Image analysis demonstrated that PAD patients with DM had significantly higher calcium burden compared to PAD patients without DM for 4 out of 5 peripheral arteries assessed (femoral-popliteal p=0.01, anterior tibial p=0.002, peroneal p=0.004, posterior tibial p=0.001). After adjusting for age, sex, and body mass index, multivariate analyses revealed that a history of CAD, dialysis dependence, and DM were significantly and positively associated with peripheral artery calcium burden. Conclusions: CT imaging allows for vessel-by-vessel calcium scoring in PAD and provides insight into the patient characteristics that may contribute to calcium burden. Future broader use of calcium scoring in PAD may allow for identification of ideal roadmaps for interventional planning, identify who is most susceptible to technical failure from interventions, and predict limb outcomes by providing quantitative data related to disease characteristics on a vessel- and lesion-specific basis.