BARCELONA (FRONTLINE MEDICAL NEWS) – Routine surgical closure of the left atrial appendage during open heart surgery provides long-term protection against cerebral ischemic events, according to the findings of the first-ever randomized controlled trial to address the issue.

“I think we can say, based on our study, that it would be advisable to routinely add surgical closure of the left atrial appendage to planned open heart surgery,” Jesper Park-Hansen, MD, said at the annual congress of the European Society of Cardiology.

New-onset atrial fibrillation is common following cardiac surgery. That’s one of the reasons why 1%-3% of patients have a stroke within the first year following coronary artery bypass graft (CABG) surgery. A clot kicked loose from the left atrial appendage (LAA) is the source of most ischemic strokes.

In light of the demonstrated success of percutaneous closure of the LAA using the Watchman and other devices for stroke prevention in patients with atrial fibrillation, Dr. Park-Hansen and his coinvestigators at the University of Copenhagen organized LAACS (the Left Atrial Appendage Closure Study). The goal was to generate solid, randomized trial evidence as to whether preemptive routine surgical closure of the LAA at the time of cardiac surgery is of benefit. Some cardiac surgeons already do this routinely; many others don’t because of the lack of Level 1 supporting evidence.

LAACS included 141 patients randomized to surgical LAA closure or not at the point of first-time open heart surgery. The study population included patients with and without a history of atrial fibrillation. LAA closure was accomplished via a purse string closure with a silk string around the neck of the appendage backed up by an additional single running suture. Transesophageal echocardiography performed in 10 patients a mean of 520 days post closure showed no signs of leakage or incomplete closure.

The primary composite outcome was comprised of clinical stroke or transient ischemic attack diagnosed by a neurologist, or a silent cerebral infarct detected on MRI performed 2-4 weeks post discharge and again at least 6 months later. At a mean follow-up of 3.7 years and a maximum of 6 years, this outcome had occurred in 6.3% of the LAAC group, significantly lower than the 18.3% rate in controls. All but one patient with a cerebral ischemic event in the control group had atrial fibrillation. The risk of an event was unrelated to whether or not a patient had a history of atrial fibrillation prior to surgery or to CHA2DS2-VASc score.

Dr. Park-Hansen emphasized that he and his coinvestigators don’t consider LAACS to be the final word on routine prophylactic appendage closure.

“This is the first randomized study. We are eager to move on to another randomized study on a larger scale. That is the next step for us,” he said.

“The challenge now – and what we will be discussing with our surgeons – is to agree on a feasible safe and effective means of left atrial appendage closure. My personal opinion is the Lariat suture delivery device or some other easily reproducible method of closure could be a good way to go,” Dr. Park-Hansen added.

The research group’s cardiac surgeons already have ruled out excision and stapling because of concerns about bleeding risk and the additional cost imposed by stapling.

Discussant Volkmar Falk, MD , commented that LAACS was too small, probably severely underpowered, should have included a preoperative MRI so investigators could reliably capture perioperative silent cerebral infarcts, and the double suture purse string is “probably not the best method” to occlude the LAA.

“LAACS addresses an important question, but alas, it does not provide the answer,” declared Dr. Falk, professor and director of the department of cardiothoracic and vascular surgery at Charité Medical University in Berlin.

Dr. Park-Hansen and Dr. Falk reported having no financial conflicts of interest.