Researchers are to investigate the safety and efficacy of performing left atrial appendage occlusion in patients at high risk for atrial fibrillation (AF) who are undergoing cardiac surgery to prevent future stroke.
Richard Whitlock (McMaster University, Ontario, Canada) outlined the approach that will be studied in the LeAAPS (Left atrial appendage exclusion for prophylactic stroke prevention) trial in a late-breaking clinical trial session at the 2022 European Association of Cardio-Thoracic Surgery (EACTS) annual meeting (5–8 October, Milan Italy).
The study follows on from LAAOS III, in which investigators studied surgical LAAO in patients undergoing valve or coronary artery bypass graft (CABG) surgery with documented atrial fibrillation or atrial flutter and a CHA₂DS₂-VASc score of two or higher, indicating an elevated risk of stroke.
The international, multicentre trial, which enrolled 4,811 patients, found that LAAO lowered the risk of stroke or systemic embolism, the primary endpoint, by 33% overall in patients with AF or atrial flutter. After the first 30 days following the procedure, patients who received LAAO were 42% less likely to suffer a stroke over long-term follow-up than those who did not receive LAAO.
Whitlock told attendees at EACTS that the focus of research will now turn to understanding the benefits of this strategy in patients with no documented AF, but who are at risk for stroke.
The trial aims to enrol up to 6,500 patients in as many as 300 centres in the USA, Canada and Europe, with follow-up every six months.
“We hope to demonstrate at the end of this that there is a reduction in ischaemic stroke or systemic thromboembolism in these patients over long-term follow-up,” Whitlock said in his presentation at EACTS. “This is a safe procedure in these patients, it is a gift that keeps on giving in AF patients and we hope to do the same for this population.”
If the trial’s result is positive, Whitlock speculated, the procedure could have the potential to prevent tens of thousands of strokes among high-risk patients. “We can take the results of LAAOS III that are applicable to 10‒15% of our patients, and we can translate that through LeAAPS, if this is positive, to more than 55% of our patients and reduce the risk of stroke in tens of thousands of patients who would have had a stroke if they had not had their left atrial appendage occluded.”