Radiofrequency and Microwave Energy Sources in Surgical Ablation of Atrial Fibrillation: A Comparative Analysis
DOI:
https://doi.org/10.1532/HSF98.20051172Abstract
Background. Due to its complexity and risk of bleeding, the Maze III procedure has been largely replaced by surgical ablation for atrial fibrillation (AF) using alternative energy sources. Radiofrequency (RF) and microwave (MW) are the most commonly used energy forms. In this study, we sought to compare these energy modalities in terms of clinical outcomes.
Methods. Two hundred five patients underwent surgical ablation of AF, from October 1999 to May 2004 at our institution via an endocardial approach. Patients were categorized into 2 groups: RF and MW. Baseline characteristics, operative details, and clinical outcomes were compared between the 2 groups. Rhythm success was defined as freedom from AF and atrial flutter as determined by postoperative electrocardiograms.
Results. One hundred twenty patients (58.5%) were ablated using RF, whereas 85 (41.5%) were ablated with MW. Most of the patients had persistent AF in both the RF and MW groups (85.7% versus 80.0%, respectively; P = .363). Intraoperative left atrial size was 6.4 ± 1.7 cm for the RF group and 6.4 ± 1.7 cm for the MW group (P = .820). Postoperative rhythm success at 6 and 12 months was 72.4% versus 71.4% (P ± .611) and 75.0% versus 66.7% (P = .909) for the RF and MW groups, respectively. Hospital length of stay was comparable for both groups (15.4 ± 14.0 versus 13.3 ± 13.9 days; P = .307). Postoperative survival at 6 months, 1 year, and 3 years was 90.4%, 89.5%, and 86.1% for RF patients compared to 87.9%, 86.5%, and 84.4% for MW patients, respectively (log rank P = .490).
Conclusions. RF and MW energy forms yield comparable postoperative rhythm success, hospital length of stay, and postoperative survival. Both sources are rapid, safe, and effective alternatives to “cut and sew” techniques for surgical treatment of AF.
References
Boriani G, Diemberger I, Biffi M, Martignani C, Branzi A. 2004. Pharmacological cardioversion of atrial fibrillation: current management and treatment options. Drugs 64:2741-62.nCox JL, Ad N, Palazzo T, et al. 2000. Current status of the Maze procedure for the treatment of atrial fibrillation. Semin Thorac Cardiovase Surg 12:15-9.nCox JL, Boineau JP, Schuessler RB, Jaquiss RD, Lappas DG. 1995 Modification of the maze procedure for atrial flutter and atrial fibrillation. I. Rationale and surgical results. J Thorac Cardiovase Surg 110:473-84.nCox JL, Schuessler RB, D'Agostino HJ Jr, et al. 1991. The surgical treatment of atrial fibrillation. III. Development of a definitive surgical procedure. J Thorac Cardiovasc Surg 101:569-83.nDoll N, Borger MA, Fabricius A, et al. 2003. Esophageal perforation during left atrial radiofrequency ablation: is the risk too high. J Thorac Cardiovasc Surg 125:836-42.nFeinberg WM, Blackshear JL, Laupacis A, Kronmal R, Hart RG. 1995. Prevalence, age distribution, and gender of patients with atrial fibrillation. Analysis and implications. Arch Intern Med 155:469-73.nGillinov M, Pettersson G, Rice TW. 2001. Esophageal injury during radiofrequency ablation of atrial fibrillation. J Thorac Cardiovasc Surg 122:1239-40.nHaissaguerre M, Jais P, Shah DC, et al. 1998 Spontaneous initiation of atrial fibrillation by ectopic beats originating in the pulmonary veins. N Engl J Med 339:659-66.nKhargi K, Hutten BA, Lemke B, Deneke T. 2005. Surgical treatment of atrial fibrillation; a systematic review. Eur J Cardiothorag Surg 27:258-65.nMelo J, Neves J, Abecasis M, Adragao P, Ribeiras R, Seabra-Gomes R. 1997. Operative risks of the maze procedure associated with mitral valve surgery. Cardiovasc Surg 5:112-6.nNatale A, Newby KH, Pisano E, et al. 2000. Prospective randomized comparison of antiarrhythmic therapy versus first-line radiofrequency ablation in patients with atrial flutter. J Am Coll Cardiol 35:1898-904.nVan Gelder IC, Crijns HJ, Tieleman RG, et al. 1996. Chronic atrial fibrillation: success of serial cardioversion therapy and safety of oral anticoagulation. Arch Intern Med 156:2585-92.nWilliams MR, Garrido M, Oz MC, Argenziano M. 2004. Alternative energy sources for surgical atrial ablation. J Card Surg 19:201-6.n
