Page 72 - ADD-ON ABLATION SURGERY IN PATIENTS WITH ATRIAL FIBRILLATION

Chapter 9
Discussion
Background
Atrial Fibrillation (AF) is a frequent and important contributor to symptoms and morbidity in patients with cardiac diseases. More than 40% of patients referred for mitral valve surgery
have continuous AF1-3. Patients who remain in AF following mitral valve surgery may have lower survival three to five years later4 compared with those in sinus rhythm (SR), although this has not been observed in all studies5.
In the presence of AF the likelihood of normal sinus SR recovery after a conventional heart operation alone ranges from 4.5 to 36% and is even more unlikely in patients with left atriomegaly6. The first-line use of antiarrhythmic drugs to control AF resulted not to be an effective strategy due to reports of limited efficacy, poor patient compliance and contraindications7. As such, AF treatment has primarily been focused on treating the underlying rhythm pathology8. Therefore, intraoperative ablation of concurrent AF during open- heart surgery (add-on surgery) is today advised in most cases9 and the so called Cox-Maze III procedure resulted to be the most effective surgical technique for treating AF and its adverse consequences of altered hemodynamics, and increased thromboembolic risk10. Nonetheless, due to its high complexity, many surgeons are reluctant to perform the full “cut and sew” Maze III operation. As a result, the newest iteration is a Maze operation using surgical ablation rather than incisions replaced by lesions being performed employing different energy source and ablation technologies.This version is sometimes called Cox maze IV11. Using a variety of energy sources and lesion sets, most groups report ablation success in 70 to 80% of mitral patients12-20.
Nonetheless, there are many aspects of add-on ablation surgery that have been poorly investigated and are the maim aims of this thesis.
First, controversy exists as to whether the considerable proportion of health care resources spent on these patients represents a cost-effective approach in an attempt to maintain a meaningful quality of life (QoL).To answer this question, we evaluated QoL and cost-effectiveness of add-on surgery.We also explored the relationship between successful SR conversion and postoperative health-related QoL. Furthermore, electrical cardioversion (ECV) is commonly recommended for patients with recurrent AF following an initial ablation procedure. Nonetheless, although the long-term effect of ECV might be promising under these
190