NEW YORK – Patients with both mitral valve regurgitation and atrial fibrillation who undergo concurrent mitral valve surgery and surgical ablation are more than twice as likely to be free of AF a year after surgery than are their counterparts who have mitral valve surgery alone, according to results of a randomized trial.
“About a quarter to a half of our your patients coming for mitral valve surgery also have AF,” Dr. A. Marc Gillinov said at the 2015 Mitral Valve Conclave sponsored by the American Association for Thoracic Surgery. “A great mitral valve repair is your first priority, but you also want to treat the AF.” Currently, cardiac surgeons perform concurrent mitral valve surgery and surgical ablation about 60% of the time in patients eligible for both procedures, he said.
Dr. A. Marc Gillinov
The American College of Cardiology/American Health Association Guidelines state that surgical ablation in patients with AF having cardiac surgery for other indications is “reasonable” – “not very strong language,” he noted, and the level of evidence for concurrent procedures is C.
That led the Cardiothoracic Surgical Trials Network to pursue the clinical trial. The investigators randomized 260 patients with persistent or long-standing persistent atrial fibrillation who needed mitral valve surgery to also undergo either surgical ablation (133) or no ablation (127). The primary endpoint was freedom from AF at both 6 months and 12 months as assessed by 3-day Holter monitoring.
Almost two-thirds (63%) of patients in the ablation group were free from atrial fibrillation at both 6 and 12 months, compared with 29% of those who had mitral valve surgery only, a highly significant difference. Dr. Gillinov described the trial population as “tougher patients” with persistent AF whose average age was around 70 years, and most had organic mitral valve regurgitation.
Results were similar whether the patients underwent pulmonary vein isolation or biatrial maze procedure (61% and 66%, respectively). One-year mortality was 6.8% in the ablation group and 8.7% in the control group, reported Dr. Gillinov, who is surgical director of the Center for Atrial Fibrillation at Cleveland Clinic.
The trial found no significant differences between the ablation and nonablation groups in major cardiac or cerebrovascular adverse events, overall serious adverse events, or hospital readmissions. The results were published prior to the Dr. Gillinov’s presentation (N. Engl. J. Med. 2015;372:1399-409).
These results debunk findings from a survey a few years ago that found cardiac surgeons avoided doing surgical ablation during mitral valve surgery because it makes the operation too complex, requires longer pump times, and raises the risk of surgery, said Dr. Gillinov. “Does ablation improve rhythm control? Yes. Does ablation increase risk? No. Does ablation improve clinical outcomes? It probably does,” he said.
The trial had some limitations, Dr. Gillinov said. Its endpoint was not a clinical outcome, although looking at stroke risk or mortality would have required thousands of patients. Also, 20% of patients did not have follow-up with the 3-day Holter test. However, previous studies have shown a strong association between surgical ablation and a reduced risk of stroke. When Dr. Jolanda Kluin of Utrecht (the Netherlands) University asked if a patient would be better off with AF or a pacemaker, Dr. Gillinov replied, “I think it’s better to have an AV sequential rhythm, but the truth is no one can answer that question without clinical data.”
The bottom line is, “if you have a patient who’s having mitral valve surgery who also has AF, do an ablation,” he said.
The study was supported by the National Institutes of Health and the Canadian Institutes of Health Research. Dr. Gillinov disclosed relationships with AtriCure, Medtronic, Edwards Lifesciences, On-X Life Technologies, Abbott, Tendyne, and Clear Catheter.