For AF, LAA Rivals Anticoagulants After Ablation

A left atrial appendage (LAA) closure device provides long-term thromboembolic protection that is equivalent to direct oral anticoagulants after ablation for atrial fibrillation (AF), along with a lower risk of bleeding, according to the multicenter, randomized OPTION trial.

Based on this trial, which is the first to compare LAA closure with oral anticoagulants for stroke prevention after ablation for AF, LAA closure should now be considered “an effective first-line option,” said Oussama M. Wazni, MD, head of the electrophysiology section at the Cleveland Clinic.

In the open-label study, conducted at 106 sites in 10 countries, 1600 patients with AF and a planned ablation were randomized. At least a moderate risk for stroke — a CHA₂DS₂-VASc score of ≥ 2 in men and of ≥ 3 in women — was an entry criterion.

In the LAA closure group, patients were treated with a proprietary device (WATCHMAN FLX, Boston Scientific). In the oral anticoagulants group, a currently marketed anticoagulant was selected by the treating investigator.

Noninferiority Established With High Confidence

For the primary efficacy composite endpoint of death from any cause, stroke, and systemic embolism, rates at 36 months were similar in the LAA closure and anticoagulation groups (5.3% vs 5.8%). This established the noninferiority of LAA closure relative to anticoagulants with a high level of significance (P

For the primary safety endpoint of nonprocedure-related major bleeding or clinically relevant nonmajor bleeding, rates were lower in the LAA closure group than in the oral anticoagulants group (8.5% vs 18.1%; P published online in the New England Journal of Medicine.

Of the 803 patients randomized to LAA closure, nine implantations were unsuccessful, and 41 patients never received the device. In the oral anticoagulants group, one patient underwent LAA closure in error, and 82 patients crossed over. At least 92% of patients in each group completed the 36-month follow up.

Baseline characteristics in the two groups were comparable. Average age was around 69 years, and about one-third of the patients were women. About 10% of the patients had experienced a previous stroke or transient ischemic attack. Prior to ablation, about 40% had persistent AF and 60% had paroxysmal AF.

Event Rates Similar in the Two Groups

Individual events in the primary composite efficacy endpoint were similar; no differences approached statistical significance. For the mortality endpoint, for example, rates of all-cause death (3.8% vs 4.5%; P = .46), cardiovascular death (1.2% vs 1.3%; P = .94), and noncardiovascular death (1.9% vs 2.6%; P = .34) were all lower in the LAA closure group than in the anticoagulants group, but statistically comparable.

Rates of ischemic stroke in the LAA closure and anticoagulants groups were similar (1.2% vs 1.3%; P = .77), as were rates of hemorrhagic stroke (0.4% vs 0.4%). The rate of systemic embolism was higher in the LAA closure group than in the anticoagulants group, but the difference was not meaningful (0.3% vs 0.1%: P = .58).

All patients received anticoagulation after ablation, but the protocol called for the discontinuation of anticoagulation in the LAA closure group after 90 days. This happened in about 80% of patients. At the end of 3 years, fewer patients in the LAA closure group than in the oral anticoagulants group remained on anticoagulation (10.1% vs 84.8%).

There were no substantial differences in the primary efficacy or safety endpoints for subgroups defined by age (≥ 75 years vs 2DS₂-VASc score (2-3 vs 4-5 vs ≥ 6), HAS-BLED score (0 vs 1-2 vs ≥ 3), or type of AF (paroxysmal vs persistent). 

LAA Performed With Ablation in 40% of Patients

In the LAA closure group, 40% of patients underwent ablation and closure of the LAA concomitantly; the remaining patients underwent LAA closure after ablation. Concomitant treatment could be an attractive strategy for patients undergoing LAA closure, Wazni pointed out.

The concomitant approach “has the potential to reduce procedural risks and recovery times for patients,” he said. “In one procedure, we have the potential to decrease AF burden and decrease the risk of stroke and bleeding.”

The use of LAA closure has been largely restricted to patients who are not good candidates for anticoagulation, based on previous studies comparing LAA closure with warfarin, such as PREVAIL, in which LAA closure did not meet the noninferiority criteria for the composite efficacy outcome, said Manesh R. Patel, MD, chief of the Division of Cardiology at the Duke University in Durham, North Carolina.

LAA closure with the device used in the OPTION study is a “reasonable option” to discuss with patients, said Patel, but he emphasized that the risk for stroke should be sufficient to warrant a prophylactic strategy. The OPTION trial was designed to evaluate LAA closure for the risk for stroke after patients had undergone ablation, not for the primary prevention of stroke in AF patients.

There will likely be more discussion on when LAA closure might be a better option than oral anticoagulants in the postablation AF patient, but Patel suggested that LAA closure could be given particular consideration in patients with heart failure.

The benefits of ablation for AF “are most evident in patients with heart failure,” he explained. “These patients often have a higher risk for stroke and systemic embolism and may be” the ideal patients for this strategy.