In patients with atrial fibrillation, surgical ablation in conjunction with cardiac surgery achieves positive immediate results, according to findings published in The Annals of Thoracic Surgery.
Moreover, AF ablation concomitant to surgery is not associated with late neurological events, even when oral anticoagulation is discontinued, researchers found.
Friederike Schlingloff, MD, of the Asklepios Klinik St. Georg in Hamburg, Germany, and colleagues evaluated 70 consecutive patients (mean age, 72.1 ± 6 years; 47% men; mean CHA2DS2-VASc score, 3.9 ± 1.8; 66% on oral anticoagulants) who underwent AF ablation and open heart surgery.
The mean operative risk of the patients was 9.7 ± 8.2%, based on EuroSCORE II; 68.6% of patients had diagnosed valve pathology.
The researchers implanted all patients with Reveal XT continuous monitoring devices (Medtronic) after the operations to accurately evaluate sinus rhythm. Paroxysmal AF was diagnosed in 22 patients (31.4%), persistent AF in 20 patients (28.6%) and long-standing persistent AF in 28 patients (40%); median AF duration time was 18 months.
The investigators collected data on cardiac rhythm via telemonitoring on a monthly basis and calculated AF burden at 3, 6, 9 and 12 months after surgery; ablation achieving an AF burden of 0.5% or less was defined as a successful procedure. Patients were interviewed by telephone 1 year after surgery to determine the incidence of neurologic or bleeding events.
Overall survival rates were 95.7% at 30 days and 84.3% at 12 months; even in high-risk surgical patients, the 30-day mortality was only 4.3%. None of the noncardiac deaths were due to neurologic events.
At 12 months, 66.7% of patients were considered responders, with stable sinus rhythm and AF burden of 0.5% or less. The proportion of responders increased from 46.3% at 3 months to 60.4% at 6 months and to 60.8% at 9 months. Additionally, AF burden of 0.5% or less at 3 months predicted ablation success at 12 months (P = .035).
Antiarrhythmic drugs had been discontinued in 88.2% of patients by the end of the study, and oral anticoagulants had been stopped in 92.1% of patients.
Although 92.8% of patients with paroxysmal AF achieved ablation success at 12 months, only 64.3% of patients with persistent AF and 54.4% of patients with long-standing persistent AF were responders. However, even nonresponders demonstrated decreased AF burden over time, dropping from a 31.7% mean burden at 3 months to a 17.1% mean burden at 1 year.
“Prospective, randomized controlled studies are needed to prove the effect of [left atrial] appendage closure on [thromboembolism] risk and the reliability of the CHA2DS2-VASc score to predict the risk of [thromboembolism] events after successful atrial ablation,” the researchers wrote. – by Jennifer Byrne
Disclosure: Schlingloff reports a financial relationship with Medtronic.