12-08-2025
Evidence-Based Guidelines Issued for LAAO Devices
Created to address the 'uncertainty and practice variation' that surrounds transcatheter left atrial appendage occlusion (LAAO), the Society for Cardiovascular Angiography and Interventions and the Heart Rhythm Society have published jointly the first set of guidelines for the use of the procedure.
'There is tremendous diversity in left atrial appendage occlusion practice regarding appropriate patients, periprocedural imaging, adjunctive medical therapy, and management of device leak and device-related thrombus,' said Andrew M. Goldsweig, MD, MS, director of cardiovascular clinical research at the University of Massachusetts-Baystate, in Springfield, Massachusetts, who led the group that wrote the recommendations.
Nonvalvular atrial fibrillation (AF) is a major risk factor for stroke, and it is a condition that affects at least 12 million individuals in the US, according to data cited in the new guidelines. Oral anticoagulation is a first-line strategy for reducing stroke risk in patients with the arrhythmia, but the benefit is potentially compromised in people at high risk for bleeding.
More Than 100K Implants Per Year and Growing
Clots associated with nonvalvular AF commonly form in the left atrial appendage. The FDA has approved two LAAO systems for the prevention of stroke: the Amplatzer Amulet (Abbott) and the Watchman (Boston Scientific). Earlier this month, the FDA announced that Boston Scientific is recalling Watchman systems that were performed without the use of positive pressure-controlled ventilation. The agency said at least 120 people have been seriously injured, and 17 have died, after undergoing the procedure.
For both systems, the current indication remains limited to people with contraindications to oral anticoagulation; however, the consensus expressed in the new guidelines is that this restriction is 'outdated' in the wake of evidence that has become available since the publication of pivotal trials that preceded approval of both available devices.
How often devices are being implanted outside current FDA labeling is unclear, but LAAO has become 'one of the most frequent procedures' in cardiology, with an estimated 100,000 performed in 2024, according to data cited by Goldsweig.
Eight evidence-based recommendations, covering patient selection, how imaging should be employed to assess and follow patients, and whether adjunctive oral anticoagulation should be considered in those with peridevice leak or device-related thrombus, were outlined in the new guidelines, which were simultaneously published in the Journal of the Society for Cardiovascular Angiography & Interventions and Heart Rhythm .
Two address patient selection. The first reiterates the current indication, which is that LAAO should be considered in patients with nonvalvular AF with a contraindication to oral anticoagulation.
The second identifies LAAO and oral anticoagulation as treatment options for patients with nonvalvular AF who do not necessarily have a contraindication to oral anticoagulation. Specifically, the guideline includes LAAO as an option for those 'with strong preferences to avoid long-term oral anticoagulation.'
Based on current evidence, 'the main point of this recommendation is that LAAO is every bit as good as OAC [oral anticoagulant] — maybe even better — in terms of preventing atrial fibrillation-associated stroke,' Goldsweig said.
Superiority for LAAO cannot be claimed because the large, randomized trials conducted to date have all employed a noninferiority design, Goldsweig acknowledged.
Although earlier noninferiority trials, such as PREVAIL, compared LAAO to warfarin, most of the patients in the comparator group in the latest of these trials received a non-vitamin K oral anticoagulant. This trial, called OPTION, published earlier this year, compared arms for noninferiority on the primary composite endpoint of death from any cause, stroke, or systemic embolism at 36 months.
Over the study period, the endpoint was reached by 8.5% in the LAAO group and 18.5% in the anticoagulation group, which easily met statistical significance for noninferiority. Superiority ( P < .001) for LAAO was also shown, but this result was hypothesis-generating given that the trial was not designed to study superiority.
Trials May Expand Indications for LAAO
Trials comparing LAAO to anticoagulant therapy as a first-line stroke prevention strategy among those who are candidates for either are underway. The CHAMPION-AF trial with the Watchman device and the CATALYST trial with the Amplatzer Amulet device in patients are in progress. Results are expected in 2026.
Three other sets of recommendations involve periprocedural imaging, which is not being employed consistently across centers performing LAAO, according to Goldsweig. In one recommendation, pre-procedure transesophageal echocardiography or CT is identified as preferable to no such imaging. In the second and third, transesophageal echocardiography or CT are recommended, respectively, during and after the procedure.
The remaining recommendations involve the use of oral anticoagulation following LAAO procedures with attention to peridevice leak and device-related thrombus, but data for these recommendations are generally limited, so they are accompanied by discussions of knowledge gaps.
The authors of the guidelines caution that the relative role of oral anticoagulation and LAAO in nonvalvular AF is an evolving area. Many of the recommendations were labelled as 'conditional' based on evidence that generated 'low certainty.'
Differences in relative acute and long-term costs, which were not addressed in the new guidelines, are another factor that might affect a stroke prevention strategy for individual patients. The Centers for Medicare and Medicaid Services announced a 27% reduction in the proposed 2026 Medicare fee schedule for the procedure. The American College of Cardiology, which attributed the proposed change to ' a proposed efficiency adjustment reduction,' is among several cardiology groups protesting the potential change.
Some interventionalists have posted on social media that they can perform the procedure in under 10 minutes and about the safety of safe-day discharge of patients — practices that suggest clinicians are becoming more efficient with LAAO. But whether those statements influenced cardiometabolic syndrome is unclear.
The expansion of LAAO past current indications is not uniformly embraced.
John M. Mandrola, MD, a clinical electrophysiologist in Louisville, Kentucky, and host of the This Week in Cardiology podcast on has been a long-time critic of LAAO. The popularity of 'this well-compensated procedure has gotten ahead of the evidence,' he said.
'For evidence-minded physicians who are concerned about the rapid rise in LAAO procedures in patients without absolute contraindications to oral anticoagulants,' the conclusion that LAAO is as good as oral anticoagulation 'is very premature,' Mandrola said.
Not least of his concerns, he noted that LAAO 'failed to show noninferiority to warfarin — a weaker comparator to the now commonly used direct-acting oral anticoagulants.'
Mandrola said most patients now undergoing LAAO would not have been eligible for the pivotal Watchman vs warfarin trials. He has repeatedly called for a more conservative approach until proper trials provide evidence of equivalence.
Mandrola said older patients with multiple competing causes of stroke — a common type of patient receiving LAAO — likely derive little to no net benefit from the focal strategy of appendage closure.
The principal investigator of the recently published OPTION trial, Oussama Wazni, MD, MBA, section head of cardiac electrophysiology and pacing at the Cleveland Clinic in Cleveland, emphasized the need to consider risks and benefits.
'I think it is reasonable to consider LAAO as an alternative to oral anticoagulation' on the basis of patient preference, he said, but only 'after a careful and thorough shared decision discussion with patients regarding the potential acute complications and the potential for leaks and device-related thrombus.'
Goldsweig, Mandrola, and Wazni reported having no relevant financial conflicts of interest.
