Atrial Fibrillation Treatment: A Shift in Perspective on LAAO?
New data from the CLOSURE-AF trial are prompting cardiologists to re-evaluate the role of left atrial appendage occlusion (LAAO) in patients with atrial fibrillation (AF) who are at high risk for both stroke and bleeding. Published in the New England Journal of Medicine, the trial surprisingly found that standard medical care, including anticoagulants, performed better than LAAO in this specific patient population.
CLOSURE-AF: Unexpected Results
The CLOSURE-AF trial enrolled 912 patients with a high stroke risk (CH2DS2-VASc score ≥ 2) and increased bleeding risk (HAS-BLED score ≥ 3, history of bleeding, or chronic kidney disease). Participants were randomized to either LAAO – primarily using Abbott’s Amplatzer Amulet or Boston Scientific’s Watchman FLX – or physician-directed standard care, which largely involved direct oral anticoagulants (DOACs). After a median follow-up of 3 years, the trial demonstrated that LAAO did not meet noninferiority criteria compared to standard care (P for noninferiority = 0.44). In fact, the adjusted hazard ratio of 1.28 (95% CI 1.01-1.62) significantly favored standard care.
Why the Surprise?
Ulf Landmesser, MD, who presented the trial results, expressed surprise, noting that this patient group is precisely where LAAO is increasingly being utilized. He indicated he would likely modify his practice based on these findings, suggesting that high-risk patients may not be the ideal candidates for the procedure. This contrasts with current guidelines, which offer a Class 2b recommendation for LAAO in this population in both the US and European guidelines.
The Ongoing Debate: Balancing Risks and Benefits
The CLOSURE-AF results highlight the importance of carefully weighing the risks and benefits of LAAO. Andrew Goldsweig, MD, emphasized that the trial captures a patient profile commonly seen in practice and mirrors those enrolled in recent trials like Amulet IDE, PRAGUE-17, and the ongoing CONFORM trial. He suggests the results may be influenced by the experience level of operators and the devices used during the trial’s enrollment period (2018-2024), and that results may differ with current devices and techniques.
Jeff Healey, MD, noted that even as oral anticoagulation is effective, discontinuation rates are common, often due to bleeding concerns. Still, CLOSURE-AF revealed an increase in the primary endpoint – stroke, systemic embolism, cardiovascular/unexplained death, or major bleeding – in the LAAO arm. A quarter of the bleeding events were periprocedural, and a significant portion of the overall difference between groups was related to cardiovascular death.
What’s Next for AF Stroke Prevention?
Researchers are continuing to investigate LAAO in different risk profiles. Ongoing trials include CHAMPION-AF and CATALYST in lower-risk patients, and LAAOS-4 in very-high-risk patients. These trials aim to refine patient selection and optimize the use of LAAO.
Did you know? The HAS-BLED score is used to assess a patient’s risk of bleeding while on anticoagulation. A higher score indicates a greater risk.
FAQ
Q: Does this imply LAAO is no longer a viable option for AF patients?
A: Not necessarily. The CLOSURE-AF trial focused on a specific high-risk population. LAAO may still be appropriate for other patients, and ongoing trials will provide further clarity.
Q: What is the CH2DS2-VASc score?
A: It’s a clinical risk stratification scheme used to estimate the stroke risk in patients with non-valvular atrial fibrillation.
Q: What are DOACs?
A: Direct oral anticoagulants are a type of blood thinner commonly prescribed for AF to reduce the risk of stroke.
Q: What is the role of ablation in AF treatment?
A: Ablation can reduce stroke risk and may allow some patients to reduce or eliminate the need for blood thinners, as highlighted by recent research.
Pro Tip: Discuss your individual risk factors and treatment options with your cardiologist to determine the best course of action for your specific situation.
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