Left Atrial Appendage Closure With WATCHMAN FLX Device vs Oral Anticoagulation in Postablation AF

A patient lying in a hospital bed.
Current guidelines recommend 5 weeks of postoperative prophylactic anticoagulation, but a new study suggests the duration of this treatment ought to be extended.
Investigators evaluated LAA closure with the WATCHMAN FLX device versus oral anticoagulation following percutaneous catheter ablation for nonvalvular AF.

The WATCHMAN FLX left atrial appendage (LAA) closure device has been shown to be a reasonable alternative to oral anticoagulation (OAC) in patients with postablation 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) was started in May of 2019. The estimated study completion date is November 2024.

The investigators sought to explore whether LAA closure with the WATCHMAN FLX device is an acceptable option to OAC following percutaneous catheter ablation in individuals with a high risk for stroke and AF. The WATCHMAN FLX device is a self-expanding nitinol-framed structure that contains fixation barbs, a distal closed end, and a permeable polyester fabric, which covers the ostium of the LAA. The device is available in 5 sizes, with diameters ranging from 20 mm to 35 mm. 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 effectiveness endpoint is stroke, both ischemic and hemorrhagic, all-cause death, or systemic embolism through 36 months following randomization. The primary safety endpoint is nonprocedural bleeding through 36 months, which is based on the International Society of Thrombosis and Hameostasis (ISTH) major bleeding or clinically relevant nonmajor bleeding definitions. The secondary safety endpoint is ISTH major bleeding through 36 months, including procedural bleeding. Additional endpoints include the individual components of the primary endpoints, disabling and nondisabling stroke, and cardiovascular or unknown and noncardiovascular death.

Patients with a CHA2DS2-VASc risk score of 2 or higher in men and 3 or higher in women who received an AF catheter ablation procedure between 90 and 180 days prior to randomization (sequential) or those who are planning to receive a catheter ablation within 10 days of randomization (concomitant) will be randomly assigned in a 1:1 ratio to the WATCHMAN FLX device or control (OAC). Those in the control group will either initiate or continue market-approved OAC therapy for the duration of the study.

A total of 1600 patients were randomly assigned to the study from 130 global investigational sites. Follow-up for patients in both the device and the control groups will take place at 3 months, 12 months, 24, and 36 months.

A major limitation of the OPTION study is the fact that it is not powered to evaluate the individual endpoints of the composite effectiveness endpoint. Since patients who received sequential and concomitant ablation procedures with WATCHMAN FLX are combined, generalizability beyond the enrolled patient population is thus limited.

The investigators concluded that patients who experience postablation AF pose a new clinical challenge in the management of stroke risk.

Disclosure: Some of the study authors have declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures. 

Reference

Wazni O, Boersma L, Healey JS, et al. Comparison of anticoagulation with left atrial appendage closure after AF ablation: rationale and design of the OPTION randomized trial. Am Heart J. Published online May 6, 2022. doi:10.1016/j.ahj.2022.05.003