The WATCHMAN FLX Left Atrial Appendage (LAA) Closure Device has been shown to be a reasonable alternative to oral anticoagulation (OAC) in patients with post-ablation atrial fibrillation (AF). These findings were published in the American Heart Journal†
The multinational, multicenter, prospective, randomized Comparison of Anticoagulation with Left Atrial Appendage Closure after AF Ablation (OPTION) trial (ClinicalTrials.gov identifier: NCT03795298) started in May 2019. The estimated completion date of the study is November 2024.
The researchers sought to investigate whether LAA closure with the WATCHMAN FLX device is an acceptable option for OAC after percutaneous catheter ablation in individuals at high risk of stroke and AF. The WATCHMAN FLX device is a self-expanding structure with a nitinol frame containing fixation barbs, a distal closed end, and a permeable polyester fabric covering the ostium of the LAA. The device is available in 5 sizes, from 20mm to 35mm in diameter. The size of the device chosen is based on the maximum diameter of the LAA ostium, as measured by transesophageal echocardiography or intracardiac echocardiography.
The primary efficacy endpoint is stroke, both ischemic and haemorrhagic, all-cause death or systemic embolism up to 36 months after randomization. The primary safety endpoint is non-procedural bleeding up to 36 months, which is based on the International Society of Thrombosis and Hameostasis (ISTH) definitions of major bleeding or clinically relevant non-major bleeding. The secondary safety endpoint is major ISTH bleeding for 36 months, including procedural bleeding. Additional endpoints include the individual components of the primary endpoints, disabling and non-disabling stroke, and cardiovascular or unknown and non-cardiovascular death.
Patients with a CH2DS2-VASc risk score of 2 or higher in men and 3 or higher in women who had an AF catheter ablation procedure between 90 and 180 days prior to randomization (sequential) or those planning to have a catheter ablation within 10 days after randomization (simultaneously) randomly assigned in a 1:1 ratio to the WATCHMAN FLX device or control (COC). Those in the control group will either initiate or continue the market-approved COC therapy for the duration of the study.
A total of 1600 patients were randomly assigned to the study from 130 study sites worldwide. Follow-up for patients in both the device and control groups is at 3 months, 12 months, 24, and 36 months.
An important limitation of the OPTION study is the lack of power to evaluate the individual endpoints of the composite efficacy endpoint. As patients undergoing sequential and concurrent ablation procedures with WATCHMAN FLX are combined, generalizability outside the enrolled patient population is thus limited.
Disclosure: Some study authors have stated affiliations with biotech, pharmaceutical and/or device companies. See the original reference for a full list of author disclosures.
Wazni O, Boersma L, Healey JS, et al. Comparison of anticoagulation with left atrial appendage closure after AF ablation: rationale and design of the randomized OPTION trial† Ben Hart J† Published online May 6, 2022. doi:10.1016/j.ahj.2022.05.003