PO-674-04 ANTICOAGULATION MANAGEMENT AND RISK OF THROMBOEMBOLISM IN HEALTHY YOUTH WITH ATRIAL FIBRILLATION: DATA FROM A MULTI-INSTITUTIONAL PACES COLLABORATIVE REGISTRY

Abstract

Stroke is a well-defined complication of atrial fibrillation (AF) in adults. However, the risk of thromboembolism and need for anticoagulation therapy in children and young adults with AF are unknown. To describe the current anticoagulation practice and assess the risk of thrombosis in children and young adults with AF across 13 pediatric heart centers. Data was obtained from the multi-institutional PACES collaborative registry on atrial fibrillation. Patients ≤ 21 years of age with documented AF of an unknown cause from January 2004 to December 2018 were included. We included patients with AF with no structural heart disease, cardiomyopathy, ventricular pre-excitation, history of open heart surgery, hypertension, or thyroid disease. Of 241 subjects, 76 were prescribed oral anticoagulation at diagnosis and an additional 15 at time of AF recurrence. Aspirin was prescribed in 66 (73%) patients, warfarin in 14 (15%), novel oral anticoagulant in 7 (8%), combined therapy in 3 (3%), and unknown in 1 (1%). In a multivariable model, patients were less likely to be anticoagulated at a freestanding children’s hospital (OR 0.44, 95%CI [0.23-0.78], p=0.005) or if they had spontaneous cardioversion (OR 0.53, 95%CI [0.29-0.96], p=0.037), and more likely if prescribed an antiarrhythmic at time of initial diagnosis (OR 1.82, 95%CI [1.01-3.3], p=0.047). There was a trend towards anticoagulation in patients presenting with asymptomatic AF (OR 0.45, 95%CI [0.19-1.03], p=0.06]). Age at diagnosis, gender, and BMI were not associated with anticoagulation status. One patient (1/241, 0.4%) was found to have left atrial thrombus confirmed by transesophageal echocardiogram at time of presentation. This patient was treated with warfarin for 3 months and repeat echocardiogram showed thrombus resolution. No patient developed thromboembolic phenomenon over a mean follow up of 2.1 ± 2.6 years. Our study is the first to demonstrate that there is large practice variation in anticoagulation management with patients treated at a free-standing children’s hospital being less likely to be anticoagulated. AF associated thrombosis is rare in children and young adults.