Achieving Metrics during Beating-Heart Ex-Maze Procedures Improves Outcomes
Background: Current surgical treatments for atrial fibrillation (AF) lack intraoperative metrics that predict long-term outcomes. The extracardiac maze (Ex-Maze) procedure is a beating-heart maze procedure that causes spontaneous conversion to sinus rhythm (SR) during lesion creation. Spontaneous conversion and confirmation of pulmonary vein exit block are 2 important predictors of long-term freedom from AF.
Methods: A beating-heart Ex-Maze procedure was performed in 54 AF patients (paroxysmal, n = 2; persistent, n = 11; longstanding persistent, n = 41) undergoing concomitant cardiac surgery (mitral valve replacement [MVR] = 23, aortic VR [AVR] = 7, coronary artery bypass graft [CABG] = 17, CABG ± AVR = 3, CABG ± MVR = 2, atrial-septal defect = 2). The Ex-Maze lesion set is a comprehensive, biatrial ablation pattern created epicardially with unipolar, radiofrequency energy applied by a vacuum-integrated device. Electrocardiogram data were collected during the procedure and at 1, 3, 6, and 12 months postoperatively; 24-hour Holter monitors data were also obtained 12 month postprocedure.
Results: Mean left atrial size was 5.4 cm. Average procedure time was 39 minutes. There were no device- or procedure-related complications. At the time of surgery 48 patients were in AF; 32 (67%) patients spontaneously converted to SR during lesion creation. At a mean follow-up of 262 days, 42 of 48 patients (88%) were free from AF, 39 of 48 (81%) were in SR; and 35 of 47 (74%) were free from AF and had discontinued class I and III antiarrhythmic drugs. In 32 of 33 patients (97%), exit block at 15 mA was confirmed, in which pulmonary vein isolation was tested. Follow-up was completed for 30 of the exit-block patients; freedom from AF was observed in 29 of 30 (97%), SR in 26 of 30 (87%), and freedom from AF and class I/III antiarrhythmic drugs in 25 of 29 (86%).
Conclusions: Recent advances in techniques and technologies permit the creation of a comprehensive biatrial lesion pattern on the epicardium of a beating heart. Observation of spontaneous conversion and confirmation of pulmonary vein exit block are important metrics that predict improved long-term outcomes.
Barnett SK, Ad N. 2006. Surgical ablation as treatment for the elimination of atrial gibrillation: a meta analysis. J Thorac Cardiovasc Surg 131:1029-35.nCalkins H, Brugada J, Packer DL, et al. 2007. HRS/EHRA/ECAS expert consensus statement on catheter and surgical ablation of atrial fibrillation: recommendations for personnel, policy, procedures and follow-up. Heart Rhythm 4(6):1-46nCappato R, Calkins H, Chen SA, et al. 2005. Worldwide survey on the methods, efficacy, and safety of catheter ablation for human atrial fibrillation. Circulation 111:1100-5.nCox JL. 2003. Atrial fibrillation I: a new classification system. J Thorac Cardiovasc Surg 126;1686-92.nCox JL, Ad N, Palazzo T et al. 2000. Current status of the maze procedure for the treatment of atrial fibrillation. Semin Thorac Cardiovasc Surg;12:15-9.nCox JL, Schuessler RB, D'Augostino HJ, et al. 1991. The surgical treatment of atrial fibrillation: III. development of a definitive surgical procedure. J Thorac Cardiovasc Surg 101:569-83.nDamiano RJ, Schuessler RB, Voeller RK. 2007. Surgical treatment of atrial fibrillation: a look into the future. Semin Thorac Cardiovasc Surg 19:39-45.nFalk RH. Atrial fibrillation. 2001. N Engl J Med 344:1067-78.nFeinberg WM, Blackshear JL, Laupacis A, Kronmal R, Hart RG. 1995. Prevalence, age distribution, and gender of patients with atrial fibrillation. Arch Intern Med 155:469-73.nGillinov AM, Blackstone EH, McCarthy PM. 2002. Atrial fibrillation: current surgical options and their assessment. Ann Thorac Surg 74:2210-17.nHaissaguerre M, Sanders P, Hocini M, et al. 2005. Catheter ablation in long-lasting persistent atrial fibrillation. J Cardiovasc Electrophysiol 16:1125-37.nHRS/EHRA/ECAS. 2007. Expert consensus statement on catheter and surgical ablation of atrial fibrillation: recommendations for personnel, policy, procedures and follow-up. Available at: http://www.hrsonline.org/News/Media/press-releases/upload/HR-and-Euro-Copy-for-Print.pdf'>http://www.hrsonline.org/News/Media/press-releases/upload/HR-and-Euro-Copy-for-Print.pdfnHynes BJ, Luck JC Wolbrette DL, et al. 2003. Atrial fibrillation in patients with heart failure. Curr Opin Cardiol 18:32-38.nJais P, Hocini M, Sanders P, et al. 2006. Long-term evaluation of atrial fibrillation ablation guided by noninducibility. Heart Rhythm 3:140-5.nKiser AC, Nifong LW, Raman J, Kasirajan V, Campbell N, Chitwood WR. 2008. Evaluation of a novel epicardial atrial fibrillation treatment system. Ann Thorac Surg 85:300-3.nKiser AC, Wimmer-Greinecker G, Chitwood WR. 2007. Totally extracardiac maze procedure performed on the beating heart. Ann Thorac Surg 84:1783-5nKosakai Y. 2000. Treatment of atrial fibrillation using the maze procedure: the Japanese experience. Semin Thoracic Cardiovasc Surg 12:44-52nLiu XK, Jahangir A, Terzic A, Gersh BJ, Hammell SC, Shen WK. 2004. Age- and sex-related atrial electrophysiologic and structural changes. Am J Cardiol 94:373-5.nMiyasaka Y, Barnes ME, Gersh BJ, et al. 2006. Secular trends in incidence of atrial fibrillation in Olmsted County, Minnesota, 1980 to 2000, and implications on the projections for future prevalence. Circulation 114:119-25.nNatale A, Raviele A, Arentz T, et al. 2007. Venice chart international consensus document on atrial fibrillation ablation. J Cardiovascular Electrophysiol 18:560-80.nOral H, Chugh A, Lemola K, et al. 2004. Noninducibility of atrial fibrillation as an end point of left atrial circumferential ablation for paroxysmal atrial fibrillation: a randomized study. Circulation 110:2797-801.nSueda T, Imai K, Orihashi K, Okada K, Ban K, Hamamoto M. 2005. Midterm results of pulmonary vein isolation for the elimination of chronic atrial fibrillation. Ann Thorac Surg 79:521-5.n
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