Chronic Atrial Fibrillation Is Associated With Reduced Survival After Aortic and Double Valve Replacement

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1 Chronic Atrial Fibrillation Is Associated With Reduced Survival After Aortic and Double Valve Replacement Richard Schulenberg, MD, Polychronis Antonitsis, MD, Andrie Stroebel, MD, and Stephen Westaby, MS, PhD Department of Cardiac Surgery, Oxford Heart Centre, John Radcliffe Hospital, Oxford, United Kingdom Background. Although chronic atrial fibrillation () is thought to negatively affect survival after aortic valve replacement (AVR), evidence is limited and intraoperative methods to restore sinus rhythm are not widely adopted. This study investigated long-term outcome in valve prosthesis patients with or without. Methods. Between 1994 and 2006, 420 patients with the same mechanical prosthesis were prospectively entered into a database; 90 had chronic preoperatively. Medical therapy was used to attempt to restore sinus rhythm postoperatively, but none had intraoperative ablation. All were anticoagulated with warfarin and monitored serially in National Health Service (United Kingdom) clinics. Survival and adverse events were determined by detailed review. Results. Mean follow-up was 79.5 months (range, 18 months to 13.5 years); 12 were lost to follow-up. Procedures included 225 AVRs with or without coronary bypass (AVR with CABG), 151 mitral valve replacements (MVR) with CABG, and 32 double-valve replacements (DVR). Preoperative patients remained in the same rhythm 6 months postoperatively. Prosthesis-related events were infrequent. For chronic patients, mortality at 10 years was greater after AVR (64.3% vs 19.2% p < 0.001), AVR with CABG (83.3% vs 21.3% p < 0.001), and DVR (80.0% vs 17.6% p < 0.001). Survival after isolated MVR or MVR with CABG (p > 0.05) was similar. Most MVR with CABG patients in sinus rhythm had acute ischemic mitral regurgitation. Greater age (p 0.001) and preoperative (p 0.02) were risk factors for death. Conclusions. Chronic negatively affects survival after AVR with or without CABG and DVR with a mechanical prosthesis. Prospective randomized evaluation of ablation is suggested for these patients. (Ann Thorac Surg 2010;89:738 44) 2010 by The Society of Thoracic Surgeons Accepted for publication Dec 9, Address correspondence to Dr Westaby, Department of Cardiac Surgery, Oxford Heart Centre, John Radcliffe Hospital, Headley Way, Headington, Oxford, OX3 9DU, United Kingdom; swestaby@ahf.org.uk. Intraoperative ablation of atrial fibrillation () pathways is increasingly recommended for valve replacement patients, but there is little evidence to support the concept that chronic negatively affects survival [1]. Current information suggests that the frequency of performance of ablation is inversely related to the presence of comorbidities or the perceived complexity of the primary procedure [2]. Because is associated with more advanced valvular heart disease and many patients require concomitant coronary bypass (CABG), an additional procedure may further increase surgical risk. As a result, sicker patients who may benefit most are least likely to undergo pathway ablation [2]. We have previously demonstrated that chronic negatively affects the ability to reverse remodel the left ventricle after aortic valve replacement (AVR) [3]. Inthe present study, we sought to define differences in survival and morbidity amongst valve replacement patients (with and without coronary disease) in sinus rhythm or chronic. This information may help determine whether concomitant pathway ablation should be considered for some or all patients in the future. Material and Methods To eliminate potential differences between patients who received anticoagulation because of or a mechanical prosthesis vs tissue valve patients without anticoagulation, we limited the study to patients with a mechanical prosthesis, all of whom were anticoagulated. We performed detailed follow-up studies on all patients who received a bileaflet pyrolytic carbon valve prosthesis (ATS Medical, Minneapolis, MN) by a single surgeon between January 1994 and January 2006 [4]. A comprehensive database already existed for these patients. Institutional review board approval was gained to use the data for research purposes, and under hospital protocol the patients consented to the collection of outcome data on their surgical consent form. In all patients designated as having chronic, the was documented in the referring cardiologist s clinic before referral for operations. A total of 420 adult patients received one or more prostheses, with or without CABG (Table 1). The mean age at implantation was years (range, 16 to by The Society of Thoracic Surgeons /10/$36.00 Published by Elsevier Inc doi: /j.athoracsur

2 Ann Thorac Surg SCHULENBERG ET AL 2010;89: POST-AVR SURVIVAL WITH Abbreviations and Acronyms atrial fibrillation AVR aortic valve replacement CABG coronary artery bypass grafting CI confidence interval DVR double valve replacement HR hazard ratio MVR mitral valve replacement sinus rhythm years). Pediatric patients were not included. In 68 patients (16%), reoperative procedures included 28 aortic valve replacements (AVR; 11 with CABG), 27 mitral valve replacements (MVR; 8 with CABG), and 30 AVR and MVR, or double-valve replacements (DVR). Operations were performed under emergency circumstances within 24 hours of presentation in 59 (14.3%). Many were highrisk procedures. For instance, there were 3 emergency reoperations for a thrombosed aortic prosthesis, 4 cases of prosthetic dehiscence due to endocarditis, and 2 aortic root reoperations where an ATS valved conduit was used. All primary MVRs for nonrheumatic disease were performed with preservation of the subvalvar apparatus in an attempt to preserve left ventricular function. None of the patients who came to their operations with had ablation by surgical or catheter-based techniques. No other patients were referred for ablation elsewhere. When postoperative developed, attempts were made to restore sinus rhythm by electrical cardioversion or drug therapy before hospital discharge. Anticoagulation was carefully monitored by National Health Service (United Kingdom) anticoagulation clinics and guided by institutional guidelines for the ATS prosthesis. Target 739 international normalized ratio (INR) was 2.0 to 2.5 for isolated AVR with or without CABG in sinus rhythm and 3.0 to 3.5 for MVR with or without CABG and DVR. For AVR with or without CABG with, the target INR was also 3.0 to 3.5. Follow-up was undertaken until July Detailed demographic outcome information was collected by retrospective review of the patient s hospital medical record. This included preoperative and postoperative electrocardiographs and echocardiographic findings by his or her cardiologist. Telephone contact was made with the patients together with the general practitioner or a close relative in the event of postoperative death. In the event of death or inability to trace a patient, information was obtained from the National Health Service Central Statistics Department and the National Registry of Births and Deaths in the United Kingdom. We recorded preoperative and postoperative rhythm status, valve-related adverse events as defined by the Society of Thoracic Surgeons (United States) database, and cause of death. Both 30-day and overall mortality during the course of follow-up were defined [2]. Continuous variables are expressed as mean standard deviation. Linearized rates are expressed in percentage per patient-year. The Kaplan-Meier method was used to determine overall survival. The log-rank test was used to provide p values for differences in survival. Univariate analysis was performed using the 2 and the log-rank tests. Categoric and continuous variables included in the univariate analysis were age, gender, and preoperative and postoperative rhythm. Multivariate analysis was performed using the Cox proportional hazard model. Hazard ratios (HR) are expressed with confidence intervals (CI). Factors with a value of p 0.05 by univariate analysis (advanced age, preoperative and postoperative rhythm) ADULT CARDIAC Table 1. Preoperative and Postoperative Patient Characteristics Variable a AVR AVR CABG MVR MVR CABG AVR MVR Patients Gender Male 125 (73.5) 49 (89) 63 (48.8) 15 (68.2) 13 (40.6) Female 45 (26.5) 6 (11) 66 (51.2) 7 (31.8) 19 (59.4) Age, y (22 88) (51 83) (15 80) (45 78) (41 49) Reoperation 17 (10) 19 (34.5) 21 (16.3) 6 (27.2) 13 (40.6) Emergency operation 32 (11.7) 7 (12.7) 9 (7.0) 7 (31.8) 4 (12.5) Follow-up, mon Rhythm status Pre-op 156 (91.8) 49 (89) 85 (65.9) 11 (50) 17 (53.1) 14 (8.2) 6 (11) 44 (34.1) 11 (50) 15 (46.9) At hospital discharge 140 (82.4) 40 (72.7) 76 (58.9) 9 (40.9) 11 (34.4) 30 (17.6) 15 (27.3) 53 (41.1) 13 (59.1) 21 (65.6) a Continuous data are shown as number (%), and categoric data as mean standard deviation (range). atrial fibrillation; AVR aortic valve replacement; CABG coronary artery bypass grafting; MVR mitral valve replacement; sinus rhythm.

3 740 SCHULENBERG ET AL Ann Thorac Surg POST-AVR SURVIVAL WITH 2010;89: were included in the multivariate analysis. Statistical significance was accepted at p Statistical analyses were performed using SPSS 16 software (SPSS Inc, Chicago, IL). Results Fully comprehensive follow-up information was available for 408 patients (Table 1). Gender distribution for each operation is reported in Table 1. Mean follow-up was months (range, 18 months to 13.5 years), with a total of 2673 patient-years, comprising 1140 for AVR, 908 for MVR, 342 for AVR with CABG, 116 for MVR with CABG and 192 for DVR. Nine patients (2.1%) were lost to follow-up. The analysis does not include two patients with combined DVR and tricuspid replacements, and one with DVR with triple CABG. Thus, outcomes were determined for patients undergoing AVR with or without CABG, MVR with or without CABG, and DVR (Tables 1 and 2). Hospital Deaths Among the 408 patients in the study, there were 28 (6.8%) postoperative (30-day) deaths (Table 2), 12 (43%) of which occurred in patients with chronic. Mortality was significantly elevated for patients after AVR with CABG and DVR (p 0.05). Of the 14 deaths after AVR with or without CABG, 11 occurred after emergency operations. After elective AVR, 1 patient died of perioperative myocardial infarction, 1 died of ventricular fibrillation after concomitant myomectomy for hypertrophic obstructive cardiomyopathy, and 1 died of bowel perforation and multiorgan failure. did not influence early death after MVR with CABG. Late Deaths Actuarial survival curves (with confidence limits) are presented for patients with and without preoperative (Figs 1 and 2). During the hospital discharge follow-up, 94 patients died (23.0%). Death occurred most frequently in ischemic cardiomyopathy patients after MVR with CABG Fig 1. Survival is shown after mitral valve replacement (MVR; black dashed line), aortic valve replacement (AVR; solid black line), AVR with coronary artery bypass grafting (CABG; gray line), MVR with CABG (dotted gray line), and double-valve replacement (AVR MVR, dash-dot line). (50% mortality; Table 2). Of the late deaths, 50 (53.2%) were cardiac related, and 19 (20.2%) were due to malignant disease. After isolated AVR, survival was 82% at 10 years, but this fell to 53% by 14 years. After AVR with CABG, 10-year survival was 73%, falling to 53% by 14 years (Fig 1). After isolated MVR, survival was 70% at 10 years falling to 48% by 14 years. In contrast, survival after MVR with CABG was only 18% at 10 years, having been 54% at 8 years. For patients who underwent DVR, survival was 50% at 10 years, falling to 42% by 14 years. Effects of No patient with preoperative chronic was in sinus rhythm at 6 months postoperatively despite electrical and pharmacologic attempts at conversion in the early postoperative period. In contrast, 92% of 318 patients who were in sinus rhythm preoperatively remained in sinus rhythm at follow-up despite episodes of in Table 2. Postoperative Mortality and Complication Rates Related to Preoperative Rhythm Status AVR (n 170) AVR CABG (n 55) MVR (n 129) MVR CABG (n 22) AVR MVR (n 32) Complication (n 156) (n 14) (n 49) (n 6) (n 85) (n 44) (n 11) (n 11) (n 17) (n 15) No. (%) No. (%) No. (%) No. (%) No. (%) No. (%) No. (%) No. (%) No. (%) No. (%) 30-day mortality 9 (5.8) 2 (14.4) 2 (4) 1 (16.7) 4 (4.7) 3 (6.8) 1 (9.1) 1 (9.1) 0 5 (33.3) Late deaths 21 (13.5) 7 (50) 10 (20.4) 4 (66.7) 18 (21.1) 13 (29.5) 6 (54.5) 5 (45.4) 3 (17.6) 7 (46.7) Overall mortality 30 (19.3) 9 (64.4) 12 (34.4) 5 (83.4) 22 (25.8) 16 (36.3) 7 (63.6) 6 (54.4) 3 (17.6) 12 (80) Cause of death Cardiac related 10 (33.3) 3 (33.3) 5 (41.7) 4 (80) 4 (18.2) 9 (56.3) 3 (42.9) 3 (50) 1 (33.3) 8 (66.7) Malignancy 8 (26.7) 2 (22.2) 1 (8.3) 1 (20) 2 (9.1) 3 (18.7) 1 (14.3) 0 1 (8.3) Other 12 (40) 4 (44.5) 6 (50) 16 (72.2) 4 (25) 3 (42.8) 3 (50) 2 (66.7) 3 (25) atrial fibrillation; AVR aortic valve replacement; CABG coronary artery bypass grafting; MVR mitral valve replacement; sinus rhythm.

4 Ann Thorac Surg SCHULENBERG ET AL 2010;89: POST-AVR SURVIVAL WITH 741 ADULT CARDIAC Fig 2. Survival is shown in relation to preoperative atrial fibrillation (; dashed line) and sinus rhythm (, black line) for (A) aortic valve replacement (AVR), (B) AVR and coronary artery bypass grafting (CABG), (C), mitral valve replacement (MVR), (D) MVR with CABG, and (E) AVR with MVR. response to the operation in the early postoperative phase. Overall mortality for patients with preoperative chronic was significantly greater after isolated AVR (64.3% vs 19.2%, p 0.001) AVR with CABG (83.3% vs 21.3%, p 0.001), and DVR (80.0% vs 17.6%, p 0.001; Fig 2). When the effects of chronic at hospital discharge were analyzed, late death was greater after isolated AVR (43.3% vs 18.6%; p 0.05), after AVR with CABG (57.1% vs 17.9%; p 0.05), and after isolated MVR (39.2% vs 22.1%; p 0.05). Cox regression analysis of risk factors for late death showed the presence of preoperative (HR, 2.12; 95% CI, 1.1 to 4.06; p 0.02) and advanced age (HR, 1.05; 95% CI, 1.02 to 1.07; p 0.001) to predict worse outcome (Table 3). Because the survival difference was greatest in the AVR patients, we sought to determine whether age and were covariates. Interestingly, the mean age was years for sinus rhythm patients vs years for patients (p 0.05). Nonetheless the HR of 2.21 for preoperative suggests this to be a powerful independent adverse prognostic factor for AVR patients. After MVR with CABG, overall survival appeared to be better in the chronic group (Fig 2). This paradox could be explained by the fact that patients with acute

5 742 SCHULENBERG ET AL Ann Thorac Surg POST-AVR SURVIVAL WITH 2010;89: Table 3. Cox Regression Analysis of Survival Prognostic Factors HR 95% CI p Value Age, 60 vs 60 y Rhythm Pre-op vs Post-op vs atrial fibrillation; CI confidence interval; HR hazard ratio; sinus rhythm. mitral regurgitation due to papillary muscle rupture or ischemic dysfunction are usually in sinus rhythm before rapid deterioration precipitates a high-risk operation. In contrast, patients with chronic mitral valve disease with an enlarged left atrium often have chronic but undergo elective mitral valve operations with CABG for concomitant coronary artery disease. However, because the numbers of patients are relatively small, statistically meaningful conclusions cannot be made. Postoperative Morbidity Late nonfatal valve-related complications included ischemic stroke in 9 patients and systemic thromboembolism in 2, all of whom had postoperative. Anticoagulationrelated hemorrhage occurred in 3 patients. Mitral valve thrombosis occurred in 2 patients with who had discontinued anticoagulation and both underwent successful reoperations. Prosthetic valve endocarditis occurred in 10 patients. Linearized rates per patient-year for thromboembolism were 0.45% for AVR, 0.88% for AVR with CABG, and 0.34% for MVR. Linearized rates per patient-year for prosthetic valve endocarditis were 0.43% for AVR, 0.3% for AVR with CABG, and 0.45% for MVR and for other complications were 0.43% after AVR. Comment Our findings illustrate the profoundly negative influence of chronic on survival after AVR and DVR, even with a second-generation bileaflet prosthesis and carefully monitored anticoagulation. Death was substantially increased despite the low overall incidence of thromboembolism, prosthetic thrombosis, or anticoagulant-related hemorrhage. The results also indicate that is associated with more advanced disease and elevated surgical risk because AVR patients with or without CABG as well as DVR patients in had substantially greater postoperative death (Fig 1). Because of this, chronic should be included in risk scoring systems to predict perioperative death. This difference did not exist for patients undergoing MVR or MVR with CABG. In fact, the patients with the poorest prognosis were those undergoing MVR with CABG who presented in sinus rhythm (Fig 1). In contrast to reports that describe outcomes after elective primary valve operations, the present study contains substantial numbers of patients at elevated risk for perioperative death [5]. Thirty percent of patients had reoperative (16%) or emergency (14%) operations, and 33% of MVR patients and 50% of MVR with CABG and DVR patients had chronic preoperatively. Because most of our patients with degenerative mitral valve disease are treated by valve repair (72% in the last 10 years), valve replacement patients often represent the higher risk end of the spectrum, such as those with acute myocardial infarction and papillary muscle rupture or dysfunction. Those with acute ischemic dysfunction (often with small left atrium and preoperative sinus rhythm) are known to have a worse long-term prognosis [6, 7]. The overall elevated mortality rate associated with could reflect the fact that patients have had more advanced heart muscle and pulmonary vascular disease and thus accrue limited long-term benefit after valve replacement [8, 9]. Loss of atrial contraction with a rapid ventricular rate response can lower cardiac output by 20% to 30% and precipitate heart failure [8]. Chronic patients did not revert to sinus rhythm with medical therapy after valve replacement, but patients in sinus rhythm before valve replacement returned to sinus rhythm after a paroxysmal episode in the early postoperative period. In a study to define determinants of reverse remodelling after AVR, we found a highly significant association between chronic or pacemaker rhythm and greater left ventricular mass index [4]. This occurred with increased left ventricular wall thickness alone (after AVR) or was combined with an enlarged ventricular cavity in the failing heart. Cavity size was not only larger, but left ventricular geometry was also altered to a more spherical shape by nonsinus rhythm. This suggests a complex adverse effect of on left ventricular mechanics after valve operations. This may compound the adverse sequelae of partial surgical disruption of the subvalvar apparatus during MVR and DVR and negate the hemodynamic benefits of modern prosthetic valves. Although we attempted to restore sinus rhythm postoperatively in all patients by pharmacologic therapy and electrical cardioversion, the ability of drugs such as digoxin or amiodarone to maintain sinus rhythm is low [10, 11]. All types of drug therapy are associated with proarrhythmic side effects such as torsade des pointes, which adversely affect the sinus rhythm conversion effect [10]. An inverse relationship exists between left atrial diameter and sinus rhythm conversion rates that accounts for the substantial incidence of preoperative and postoperative atrial fibrillation in MVR and DVR patients where prosthetic replacement is necessary [12]. However, some patients with mitral regurgitation and only a short duration of preoperative will enjoy sustained freedom from after correction of the valve lesion alone. To date, information on the negative effect of persistent on survival after valve operations is limited [1, 13]. As a result, the well-established but time-consuming surgical methods to ablate and restore sinus rhythm have not been widely adopted. The cut and sew Cox Maze procedure, which creates a well-defined pattern of left and right atrial incisions to interrupt the multiple wavelet macro reentry circuits, provides a 97% to 99% success

6 Ann Thorac Surg SCHULENBERG ET AL 2010;89: POST-AVR SURVIVAL WITH rate and is considered the gold standard [14, 15]. However, the added duration of myocardial ischemia in conjunction with valve and coronary operations is considered a drawback for high-risk patients. Thus, radiofrequency ablation and cryoablation are among the less invasive methods that have emerged [16, 17]. Khargi and colleagues [18] performed a systematic review of ablation publications to compare the outcome of the Cox Maze 3 technique with the alternatives [18]. The postoperative sinus rhythm rates were 85% for the Cox Maze operation and 78% for the alternative methods (p 0.03). However, the Cox Maze procedure was conducted in younger patients (55 vs 61 years; p 0.005) and more often to treat paroxysmal (23% vs 8%) and lone (19.3% vs 1.6%). Alternative energy sources were used to treat permanent patients (92%) as a concomitant surgical procedure (98%) increasingly in combination with nonmitral operations (18.5%). When corrected for these variations, the postoperative sinus rhythm conversion rates did not differ between techniques (p 0.26). The Khargi group have shown unipolar endocardial radiofrequency ablation is as effective in permanent patients undergoing MV operations, AVR, or CABG, even though the latter patients tended to be older and with a smaller left atrial size [19]. Concomitant antiarrhythmic operations were equally safe and effective in combined valve and CABG procedures, except in those who have impaired left ventricular ejection fraction ( 0.44) and an enlarged left atrium ( 52.0 mm). Others have achieved sinus rhythm conversion rates of about 85%, although not when the left ventricular ejection fraction is less than 0.40 with an enlarged left atrium. The decision to prolong cardiopulmonary bypass in these circumstances must be made with caution [20, 21]. Nevertheless, the markedly different survival between and sinus rhythm patients may justify ablation. We reported favorable early experience with the ATS prosthesis in 1996 [4]. Since then, no structural failures have occurred in more than 170,000 implants and relatively low levels of anticoagulation (INR 1.5 to 2.5) have been shown to be effective after AVR [22, 23]. Even more remarkable is the long-term safety of well-monitored anticoagulation and the overall low risk of prosthesis related complications as described in other reports [22, 23]. From this study, it is impossible to separate the adverse effects of chronic from its presence as a marker of advanced cardiac disease [24]. Nevertheless, these outcomes indicate the need for a prospective randomized study to determine whether concomitant ablation will improve survival for valvular heart disease patients who present for operations in. Because the case series began in 1994, the patients did not undergo routine risk assessment by the Parsonnet score or the European System for Cardiac Operative Risk Evaluation, and the absence of multiple preoperative variables restricts our ability to draw reliable conclusions. For instance, we are unable to define whether the patients were at increased risk of late death through comorbidity. Also for many patients, precise cause of death could not be defined because an autopsy was not performed and certifications of death simply stated heart failure, valvular heart disease, or myocardial infarction. Similarly, it may not be possible to ascertain the true incidence of valve-related events for patients who died from the hospital records, and these may be underestimated. Because we were late to adopt intraoperative ablation (2006), we do not have a control group that received ablation and continued in sinus rhythm. References Handa N, McGregor CA, Davidson GK, et al. Valvular heart operation in patients with previous mediastinal radiotherapy. Ann Thorac Surg 2001;71: Gammie JS, Haddad M, Milford-Beland S, et al. Atrial fibrillation correction surgery: lessons from the Society of Thoracic Surgeons National Cardiac Database. Ann Thorac Surg 2008;85: Jin XY, Pillai R, Westaby S. Medium term determinants of left ventricular mass index after stentless aortic valve replacement. Ann Thorac Surg 1999;67: Westaby S, Van Nooten G, Sharif H, Pillai R, Caes F. Valve replacement with the ATS open pivot bileaflet prosthesis. Eur J Cardiothorac Surg 1996;10: Emery RW, Van Nooten GJ, Tesar PJ; investigators for the ATS Clinical Open Pivot Heart Valve Food and Drug Administration Study. The initial experience with the ATS Medical cardiac valve prosthesis. 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7 744 SCHULENBERG ET AL Ann Thorac Surg POST-AVR SURVIVAL WITH 2010;89: Mack CA, Milla F, Ko W, et al. Surgical treatment of atrial fibrillation using argon-based cryoablation during concomitant cardiac procedures. Circulation 2005;112(suppl I)I Khargi K, Hutten BA, Lemke B, Deneke T. Surgical treatment of atrial fibrillation: a systematic review. Eur J Cardiothorac Surg 2005;27: Khargi K, Deneke T, Haardt H, et al. Saline-irrigated, cooled-tip radiofrequency ablation is an effective technique to perform the maze procedure. Ann Thorac Surg 2001;72:S Bando K, Kobayashi J, Kosakai Y, et al. Impact of Cox maze procedure on outcome in patients with atrial fibrillation and mitral valve disease. J Thorac Cardiovasc Surg 2002;124: Abreu Filho CA, Lisboa LA, Dallas LA, et al. Effectiveness of the maze procedure using cooled-tip radiofrequency ablation in patients with permanent atrial fibrillation and rheumatic mitral valve disease. Circulation 2005;112(9 suppl): Van Nooten GJ, Van Belleghem Y, Caes F, et al. Lower intensity anticoagulation for mechanical heart valves: a new concept with the ATS bileaflet aortic valve. J Heart Valve Dis 2003;12: Baykut D, Grize L, Schindler C, Keil AS, Bernet F, Zerkowski HR. Eleven-year single-center experience with the ATS open pivot bileaflet heart valve. Ann Thorac Surg 2006;82: Ryder KM, Benjamin EJ. Epidemiology and significance of atrial fibrillation. Am J Cardiol 1999;84:113 38R. Requirements for Maintenance of Certification in 2010 Diplomates of the American Board of Thoracic Surgery (ABTS) who plan to participate in the 2010 Maintenance of Certification (MOC) process as Certified-Active must hold an unrestricted medical license in the locale of their practice and privileges in a hospital accredited by the JCAHO (or other organization recognized by the ABTS). In addition, a valid ABTS certificate is an absolute requirement for entrance into the Maintenance of Certification process. If your certificate has expired, the only pathway for renewal of a certificate is to take and pass the Part I (written) and the Part II (oral) certifying examinations. The CME requirements are 90 Category I credits earned since January 1, At least half of these CME hours need to be in the broad area of thoracic surgery. Category II credits are not allowed. Interested individuals should refer to the Board s website for a complete description of acceptable CME credits. Diplomates who hold certificates that end in 2010 or 2011 will be required to complete all sections of SESATS after their applications have been approved. It is not necessary for Diplomates to purchase SESATS individually because it will be sent to them after their application has been approved. Diplomates who hold certificates that end in 2012 will be required to take and pass a secured exam after their application has been approved. Taking SESATS in lieu of the secured exam is not an option. The secured exam will be given in an electronic format at testing centers located throughout the United States. Diplomates who wish to maintain a Certified-Active status will be required to submit a summary of cases and will be required to participate in an outcomes database. For more details about this requirement, please visit the Board s website at Diplomates may apply for Maintenance of Certification in the year their certificate expires, or if they wish to do so, they may apply up to two years before it expires. However, the new certificate will be dated 10 years from the date of expiration of their original certificate or most recent recertification certificate. In other words, going through the Maintenance of Certification process early does not alter the 10-year validation. Diplomates certified prior to 1976 (the year that time-limited certificates were initiated) are also required to participate in MOC if they wish to maintain valid certificates. The deadline for submitting an application for Maintenance of Certification is March 1, A brochure outlining the rules and requirements for Maintenance of Certification in thoracic surgery is available on the Board s website at For additional information, please contact the American Board of Thoracic Surgery, 633 N St. Clair St, Suite 2320, Chicago, IL 60611; telephone (312) ; fax (312) ; info@abts.org by The Society of Thoracic Surgeons Ann Thorac Surg 2010;89: /10/$36.00 Published by Elsevier Inc