SAfety of Fondaparinux in transoesophageal echocardiography-guided Electric cardioversion of Atrial Fibrillation (SAFE-AF) study: A pilot study

Abstract

Background: Current guidelines recommend unfractionated heparin (UFH) or low-molecular-weight heparin plus an oral anticoagulant for the prevention of thromboembolism in patientsundergoing electric cardioversion of atrial fibrillation (AF). Selective factor Xa inhibitors, suchas fondaparinux, which has a favourable benefit-risk profile in the prevention and treatmentof venous thromboembolism and the management of acute coronary syndromes, have not beensystematically evaluated in this setting.Aim: To evaluate the efficacy and safety of fondaparinux versus standard treatment inpatients undergoing echocardiographically-guided cardioversion of AF. Methods: In this multicentre, randomized, open-label, controlled, two-parallel-group, phaseII pilot study, patients with AF undergoing electric cardioversion following transoesophagealechocardiography (TEE) were randomized to fondaparinux or standard therapy (UFH plus vitaminK antagonist [VKA]). Patients showing an atrial thrombus in the first TEE (clot-positive) wererandomized to treatment with fondaparinux or standard care for 4 weeks before cardioversion. Results: The primary endpoint (combined rate of cerebral neurological events, systemicthromboembolism, all-cause death and major bleeding events) occurred in 3 of 174 (1.7%)patients on fondaparinux and 2 of 170 (1.2%) patients on UFH + VKA. The rate of thrombus dis-appearance among clot-positive patients was higher in the fondaparinux arm (11 of 14; 78.6%)than in the UFH + VKA arm (7 of 14; 50.0%). Incidences of adverse events were similar (45.4%with fondaparinux and 46.5% with UFH + VKA). Conclusion: In this pilot study in patients with TEE-guided cardioversion, the use of fonda-parinux appeared to be well tolerated, with similar efficacy to UFH + VKA. Furthermore, a trendto greater thrombus resolution was observed.