LAUSR

Possible antithrombotic effect of anticoagulants in coronary artery disease have been proposed but mechanism are poorly understood. Experimental and clinical data indicate a key role of coagulation factors in the progression of atherosclerosis. We sought to evaluate the effect of different oral anticoagulation agents on the progression of atherosclerosis. This retrospective matched case controlled study included patients with atrial fibrillation (AF) who underwent repeated CT angiography for ablation planning. Patients with known structural cardiac pathologies or significant comorbidities were excluded. Patients were stratified according to their anticoagulation into 3 groups: vitamin K antagonist (VKA), direct oral anticoagulation (DOAC) and control (CR; aspirin or no therapy) with equal distribution of age and cardiovascular risk factors. Baseline and follow-up CT exams for repeated AF ablations were evaluated for the CAD profile and (semi)automated quantitative plaque analysis. One-hundred sixty-one patients were included (mean CT time interval: 31 months). The three cohorts did not differ in patient characteristics or CT findings at baseline. Absolute plaque volume progression was significantly higher in patients using VKA (66.5±136.7 mm3) compared to both CR (27.2±73.6 mm3) and DOAC (−7.1±42.1 mm3, p<0.001), translating into an annual change of 23.2±47.0 mm3 for VKA, 12.3±4.3 mm3 for CR and −4.6±22.9 mm3 for DOAC (p=0.003). The number of affected segments (SIS) increased by 1.2±1.3 compared to 0.6±1.3 in the control group and 0.2±0.7 in the DOAC group (p<0.0001). Baseline CTA findings Control (n=61) DOAC (n=50) VKA (n=50) p Vessel Volume (mm3) 26.9±42.9 23.1±43.3 27.9±40.7 0.85 Lumen Volume (mm3) 15.7±24.8 13.3±25.1 16.6±27.0 0.82 Coronary Calcium Score (AU) 63.4±187.2 42.0±114.6 53.8±118.6 0.75 Segment Involvement Score 1.8±2.1 1.8±2.3 1.9±2.2 0.96 Stenosis Average Area (%) 19.0±21.7 0.5±0.7 0.5±0.7 0.71 Maximal Plaque Thickness (mm3) 0.5±0.7 0.5±0.7 0.5±0.7 0.69 Total Plaque Volume (mm3) 33.6±60.0 30.0±55.6 34.2±48.0 0.92 AU, Agatston units; DOAC, direct oral anticoagulation; SIS, segment involvement score; VKA, vitamin K antagonist. Changes between baseline and follow-up In serial coronary CTs, patients using vitamin K antagonists showed the highest plaque volume progression while patients using a direct oral anticoagulant showed a regression of total plaque volume. Therefore, direct anticoagulation may have a beneficial effect on atherosclerosis.