Commentary from the Section Editor - The Convergent Procedure: A Collaborative Atrial Fibrillation Treatment

DOI: 10.19102/icrm.2011.020506

Samuel J. Asirvatham, MD, FHRS, FACC

Editor-in-Chief

The Convergent Procedure: A Collaborative Atrial Fibrillation Treatment

In this issue of Innovations in Cardiac Rhythm Management, Drs. Kiser, Landers, and Mounsey present in the “Innovative Techniques” section an illustrative case and enlightening discussion of a unique hybrid epicardial and endocardial procedure for persistent atrial fibrillation.

Despite the strides made and advances that were essentially unthinkable 20 years ago in the invasive management of atrial fibrillation, persistent and chronic forms of AF remain unsolved problems. The plethora of researched and reported approaches claiming to have made in-roads into this vexing arrhythmia (fragmented signals, autonomic modulation, maze-like procedures…) all are testament to the increasingly recognized fact that we do not have a reliable and consistent approach that works for persistent AF.

Although epicardial approaches and various hybrid approaches have been explored for solving this problem, the “convergent procedures” reported by Kiser et al exemplifies the type of innovation needed in this arena.

1. Innovative collaboration. This technique is typical of successful collaboration where the strengths of one approach compliment the weaknesses of another. Linear ablation at certain locations, such as on the cavotricuspid isthmus or related to the crista terminalis, is very difficult from an epicardial approach while ablation of the fat pads and complete posterior left atrial isolation is highly challenging from an endocardial perspective.

2. Pericardioscopy. With their meticulously described technique, the authors illustrate the importance of visualization, reproducible visualization, access to the pericardial space, and the use of the central fibrous body to cross into the pericardial space, potentially minimizing complications (hepatic injury, pneumothorax, etc).

3. Enhancement and facilitation of future innovation. With their technique, the authors target the periatrial autonomics but using only visualization of the fat pads. Their technique, however, may enable other innovations that involve direct recording of ganglia signals and novel methods to “ablate” the ganglia without myocardial injury.

4. Remaining problems. Even in this illustrative example, the patient did have eight hours of atrial fibrillation. While the authors correctly point out that this was largely irrelevant given the symptomatic improvement the patient experienced, it serves as an important reminder that cure for atrial fibrillation is not a realistic goal for any existing or contemplated procedure.

Linear ablation, endocardial or epicardial, is a poor surrogate for the cut-and-sew line seen with the classical maze procedure. Small gaps may give rise to persistent flutter, and larger studies with long term followup are needed to know how often these occur and offset the gains in minimizing atrial fibrillation. Importantly, however, as stressed by the authors, this new technique allows specific testing of continuity and transmurality of linear ablation and electrophysiology testing typically not done with pure surgical procedures. Finally, although a justifiable rationale may exist, the choice of “lines” done with any innovative approach is largely empirical. Controlled studies, possibly translational, are needed to know exactly how much and where lesions and lines are needed (coronary sinus debulking?) that may allow minimizing complications while maintaining reasonable efficacy.

Samuel J. Asirvatham, MD, FHRS, FACC
E-mail: asirvatham.samuel@mayo.edu
Consultant, Division of Cardiovascular Diseases
and Internal Medicine, Division of Pediatric Cardiology
Professor of Medicine and Pediatrics
Mayo Clinic College of Medicine
Rochester, MN