NEW YORK — Radiofrequency ablation and cryoablation had similar efficacy and safety for treating atrial fibrillation with a modified maze procedure in a randomized, controlled study in 50 patients.
This is among the first reported studies to compare two ablation methods for treating atrial fibrillation, Piotr Suwalski, M.D., said at the annual meeting of the International Society for Minimally Invasive Cardiothoracic Surgery.
The results suggest that the two technologies are similar, although the study would have been more definitive if it had involved a larger number of patients, commented Ralph J. Damiano Jr., M.D., chief of cardiac surgery at Washington University, St. Louis.
From January 2003 to January 2004, 50 consecutive patients with atrial fibrillation who also required mitral valve surgery were randomized to either of two ablation methods.
The 26 patients who underwent the cryoablation procedure were treated with a liquid nitrogen-cooled device that was designed and built by Dr. Suwalski and his associates at the Medical University of Warsaw. The 24 patients randomized to radiofrequency ablation were treated with an irrigated radiofrequency device that was manufactured by Medtronic Inc.
The two groups of patients were well matched for demographic and clinical features.
The average durations of cardiopulmonary bypass, cross-clamp time, and ablation treatment were also very similar between the two groups.
The modified maze procedure took a mean of 18 minutes in the cryoablation group and 14 minutes in the radiofrequency group, said Dr. Suwalski, a cardiac surgeon at the Medical University of Warsaw.
The two groups also had virtually identical averages for time of intensive care hospitalization and total hospitalization time. There was one death in each group but no other major adverse coronary events or cerebrovascular events.
At 3 months after surgery, 72% of patients in the cryoablation group and 80% in the radiofrequency ablation group were in sinus rhythm.
One year after surgery, the prevalence of sinus rhythm was 75% and 82%, respectively, in the cryoablation and radiofrequency ablation groups.