Debate Leaves Little Doubt of LAA Closure Efficacy in the Prevention of Stroke in AF Patients

San Francisco, CA—A session meant to serve as a great debate on the value of left atrial appendage (LAA) occlusion vs. anticoagulant treatment for atrial fibrillation (AF) left many audience members unmoved from their established belief that LAA closure is an effective frontline stroke prevention treatment for patients with AF compared with anticoagulant therapy.

By a show-of-hands vote, when asked if prior to hearing the arguments for and against LAA closure, the audience thought it was a niche procedure to be used only in very rare cases where nothing else works, very few hands were raised. When asked if prior to hearing the talks, LAA was a mature procedure that should be discussed with the majority of patients with AF, the majority of audience members raised their hands. After the talks, when asked if the audience believed LAA is a niche procedure, no hand was raised, whereas the majority continued to believe that LAA was a mature procedure. 

LAA occlusion established

Arguing in favor of LAA occlusion, Matthew J. Price, MD, of the Scripps Clinic in La Jolla, Calif., said the verdict on LAA occlusion for AF is in. “LAA occlusion is a reasonable alternative to oral anticoagulant therapy for stroke prevention in AF in appropriate patients,” Price said. 

Randomized clinical trials to date have shown the efficacy of the procedure to be at least noninferior compared with anticoagulant treatment. He also said that the trials have confirmed the LAA hypothesis: patients who have the procedure will not be at risk for stroke. He cited data from the AVERROES, WOEST, PROTECT AF and PREVAIL trials to support his argument for LAA closure.

“When you look at the terminal therapy data in PROTECT AF … and the remarkable reduction in CV death from stroke or systemic embolism with the Watchman device, this supports the contention that occluding the LAA gets the job done and reduces your risk for bleeding,” Price said. “Our patients are living for years and years, decades and more.”

Pharmacotherapy remains standard of care

Arguing in favor of pharmacotherapy in the debate, Christopher Granger, MD, of the Duke Clinical Research Institute, Durham, N.C., said there is not currently a confidence interval at which clinicians should be comfortable enough in treating a major population at high risk for stroke. 

Granger stated that warfarin is the current standard and has been well-established to reduce the risk of stroke by two-thirds. Furthermore, he said there is a large body of evidence that newer oral anticoagulant therapies are as good as or better than warfarin at preventing stroke, with a lower risk of intracranial hemorrhage.

In making his case for anticoagulant therapy as the standard of care, he cited data from the AVERROES and PREVAIL trials.

“In comparing the trials of the newer antithrombotic therapies vs. warfarin, there was a 21% to 34% reduction in stroke [or systemic embolism], and we have a fairly compelling reduction in mortality. 

“We have this compelling data with novel anticoagulants, with lots of patients showing it is better than warfarin [and] well tolerated, and there is simply a less robust data set for LAA [closure],” Granger said. “We also have the issue of safety, granted, not surprisingly improving with experience, but nevertheless, there are unresolved issues around safety.”

Disclosures:

Price has received grant research support to his institution from SentreHeart; and consulting fees/honoraria from Boston Scientific Corporation, Janssen Pharmaceuticals, St. Jude Medical and W.L. Gore & Associates.

Granger reports research contracts with Astellas, AstraZeneca, Boehringer Ingelheim, Bristol-Myers Squibb, GlaxoSmithKline, Merck, Novartis, Sanofi-Aventis and The Medicines Company; and receiving consultant fees/honoraria from AstraZeneca, Boehringer Ingelheim, Bristol-Myers Squibb, GlaxoSmithKline, Novartis, Pfizer, Roche, Sanofi-Aventis and The Medicines Company.