**Surgical Treatment of Atrial Fibrillation Surgical Treatment of Atrial Fibrillation**

Claudia M. Loardi, Marco Zanobini and Francesco Alamanni Claudia M. Loardi, Marco Zanobini and Francesco Alamanni

Additional information is available at the end of the chapter Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/intechopen.76700

#### **Abstract**

Atrial fibrillation represents the most common supraventricular arrhythmia above all in patients undergoing cardiac surgery and is associated to an augmented risk of thromboembolic stroke, heart failure, and cardiovascular mortality. That is the reason why cardiac surgeons began to address their attention to how to surgically treat fibrillating patients according to pathophysiological models describing mechanisms of arrhythmia induction and maintenance. A new branch of cardiac surgery was born, leading to a progressive development of adapted surgical ablation techniques, applicable both to lone or concomitant arrhythmia treatment. Historical evolution and current available surgical treatment options are described, beginning from the first pure surgical maze, going through all its modifications in source ablation energies and lesion sets and finishing with current mini-invasive hybrid treatment of lone atrial fibrillation. Indications, patients' selection, technical options with respective advantages and disadvantages, surgical technique details, complications, and results are fully illustrated. Relationship between pathophysiologic arrhythmia mechanisms and the consequent ablation tailored procedure choice is highlighted, allowing a customized procedural offer to every single patient, resulting in a success rate ranging from 60 to 90%.

DOI: 10.5772/intechopen.76700

**Keywords:** atrial fibrillation treatment, maze procedure, hybrid ablation, energy sources, cardiac surgery

#### **1. Introduction**

Atrial fibrillation (AF) is a common medical condition affecting over 5 million people in the United States and whose prevalence is expected to join over 12 million by 2030. Considering people aged more than 80 years, about 7% experiences at least one episode of such supraventricular arrhythmia in their life. Dangers of AF are well known; they range from troubling symptoms to a fivefold increased risk of thromboembolic stroke and heart failure and

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

culminate in excess mortality [1]. Cardiac surgeons are frequently faced to AF, since data from the Society of Thoracic Surgeons (STS) database demonstrate that preoperative AF is present in 11% of patients presenting for nonemergent, first-time cardiac surgery, varying from 6.5% of coronary patients until nearly 30% in mitral ones [2]. The high AF prevalence in case of mitral stenosis or regurgitation may be explained by histological modifications occurring in enlarged left atria suggesting chronic inflammation and interstitial fibrosis which translate into electrical changes such as augmentation of effective atrial refractory period and conduction heterogeneity able to lead to an increased vulnerability to arrhythmia genesis. These epidemiologic considerations explain why, historically, cardiac surgeons were the pioneers of curative ablation of AF; their interest began in the 1980s when Cox and associates introduced the left atrial isolation procedure in dogs. A new branch of cardiac surgery was born, leading to a progressive development of adapted surgical ablation sets of lesions and devices, applicable both to lone and concomitant (a term indicating patients in whom AF is associated with another cardiac disease requiring surgery) arrhythmia treatment.
