Robotic Mitral Valve Repair for Simple and Complex Degenerative Disease Midterm Clinical and Echocardiographic Quality Outcomes

Transcription

1 Robotic Mitral Valve Repair for Simple and Complex Degenerative Disease Midterm Clinical and Echocardiographic Quality Outcomes Rakesh M. Suri, MD, DPhil; Amit Taggarse, MD; Harold M. Burkhart, MD; Richard C. Daly, MD; William Mauermann, MD; Rick A. Nishimura, MD; Zhuo Li, MSc; Joseph A. Dearani, MD; Hector I. Michelena, MD; Maurice Enriquez-Sarano, MD Background Severe primary (degenerative) mitral regurgitation (MR) is repaired with durable results when simple single-scallop disease is addressed. The midterm quality outcomes of minimally invasive repair for complex disease are unknown, however. Methods and Results From January 2008 to January 2015, 487 patients (56±11 years, 360 men, ejection fraction 65±6%, 98.8% complete follow-up) underwent robotic mitral valve repair for severe nonischemic degenerative MR. Simple pathology was addressed in 289 of 487 (59%) patients, and complex repair (all others) was performed in 198 of 487 (41%). Four patients died during follow-up with a 5-year survival rate 99.5% (99.4% simple; 99.5% complex; hazard ratio, 0.48; 95% confidence interval, ); and New York Heart Association functional class I/II was documented in 97.9% (477/487). Eight patients had recurrence of moderate-to-severe MR (4 simple, 4 complex), with a 5-year freedom from MR of 94.6% (96.2% simple; 92.7%, complex; P=0.67; hazard ratio, 1.36; 95% confidence interval, ). Seven patients (2 simple, 5 complex), underwent mitral reoperation, with a 5-year freedom from reoperation of 97.7% (99.1% simple; 95.7% complex; P=0.13; hazard ratio, 3.35; 95% confidence interval, ). Conclusions At a large tertiary care referral center, midterm quality outcomes after robotic correction of degenerative MR are excellent, with very high survival, infrequent complications, and a low likelihood of MR recurrence, regardless of mitral valve repair complexity. Awareness of these improvements in outcome is important to inform contemporary decisions regarding high-quality alternatives to conventional and percutaneous mitral repair. (Circulation. 2015;132: DOI: /CIRCULATIONAHA ) Key Words: mitral valve mitral valve annuloplasty prolapse quality improvement Prompt surgical correction of severe degenerative mitral regurgitation (MR) neutralizes excess mortality and heart failure risks associated with this condition. 1,1a Despite guideline support for early surgery repair in stage C1 patients (asymptomatic without left ventricular dysfunction) where mitral valve repair expertise exists, 2 patients favor less invasive therapeutic approaches to minimize postoperative debility. Recent evidence suggests that some degree of inevitable compromise exists in deciding between treatment alternatives conventional open chest surgery is highly effective in nearly all cases of degenerative MR with minimal residual regurgitation, but requires an inpatient hospital stay of 7 days, 3,4 whereas percutaneous alternatives such as MitraClip allow quicker healing at the expense of greater degrees of residual regurgitation. 5 A third option, minimally invasive surgical mitral repair, has recently gained attention, enabling the performance of complete surgical correction through very small ports; however, uncertainty regarding the consistency and durability of clinical results remains. The lack of midterm clinical and echocardiographic follow-up outcome data has thus limited the widespread recommendation of this approach. In addition, although the 2014 American College of Cardiology (ACC)/American Heart Association (AHA) Heart Valve Guidelines suggest that MR caused by posterior mitral leaflet prolapse, or simple disease, is reliably addressed by using both conventional and less invasive approaches, the recurrence of MR following repair of complex mitral disease (severe multiscallop myxomatous degeneration, anterior leaflet involvement), has traditionally been higher. 2 This has both tempered the class IIa recommendation for early intervention in these patients and cast doubt on the ability of less invasive approaches to effect complete and durable correction of complex degenerative disease subsets. Editorial see p 1941 Clinical Perspective on p 1968 Received June 4, 2015; accepted October 2, From Divisions of Cardiovascular Surgery (R.M.S., A.T., H.M.B., R.C.D., J.A.D.), Anesthesiology (W.M.), Cardiovascular Diseases (R.A.N., H.I.M., M.E.-S.), and Biomedical Statistics and Informatics (Z.L.), Mayo Clinic, Rochester, MN. Presented at the 95th Annual Meeting of the American Association for Thoracic Surgery, Seattle, WA. Correspondence to Rakesh M. Suri, MD, DPhil, Department of Thoracic and Cardiovascular Surgery, Cleveland Clinic Foundation, 9500 Euclid Ave J4-1, Cleveland, OH surir@ccf.org 2015 American Heart Association, Inc. Circulation is available at DOI: /CIRCULATIONAHA

2 1962 Circulation November 24, 2015 We hypothesized that, because of recent improvements in the understanding of mitral prolapse anatomy, 6,7 along with the standardization of repair techniques and port-based approaches, contemporary robotic mitral repair may now be capable of avoiding historic quality compromises that have previously plagued previous less invasive degenerative MR therapies. The aim of this study was thus to analyze midterm quality outcomes after simple versus complex robot-assisted mitral valve repair for primary degenerative mitral valve disease with specific focus on (1) MR recurrence, (2) mitral valve reoperation, and (3) clinical consequences, including symptoms and survival. Methods From January 2008 to January 2015, 520 robotic cardiac procedures were performed at Mayo Clinic in Rochester, Minnesota, of which 487 patients (56±11 years, 360 men, ejection fraction 65±6%) underwent robotic mitral valve repair for nonischemic degenerative severe MR and consented to have their clinical records included in observational outcomes research studies. Our program used a 2-surgeon approach during the cardiac ischemic period of robotic mitral valve repair cases as described previously, 8 and repairs were performed by 2 of the 3 participating surgeons in each case (Dr Burkhart [414 85%], Dr Daly [73 15%], and Dr Suri [ %]). Patients with mitral valve pathology caused by congenital, rheumatic, or ischemic disease; patients with active endocarditis; or those undergoing concomitant cardiac surgical procedures other than atrial septal defect/ patent foramen ovale closure or maze/modified maze procedures were not included in the current report. The only routine exclusions for robotic mitral valve repair were (1) coronary artery disease requiring revascularization, (2) severe peripheral vascular disease precluding safe groin cannulation, or (3) previous median sternotomy or right thoracotomy. Patients with evidence of >50% diameter stenosis of a coronary vessel on computerized tomography scan underwent cardiac catheterization to confirm the absence of severe coronary disease before robot-assisted mitral valve repair. No additional systematic exclusion criteria were used for patient selection, and, in particular, all categories of leaflet prolapse complexity were equally considered as appropriate candidates for robotic repair. The study was approved by the Mayo Clinic Institutional Review Board, and all patients provided informed consent for their data to be used for study purposes. Patients with mitral leaflet prolapse and severe MR were offered surgery in accordance with current ACC/ AHA guidelines. All patients underwent (1) preoperative computerized tomography angiogram and (2) preoperative transthoracic echocardiography to complete the preoperative assessment of surgical candidacy. Mitral valve prolapse anatomy and repair quality were assessed intraoperatively via transesophageal echocardiogram in all cases. Repair quality was again assessed before dismissal from the hospital following the use of transthoracic echocardiography. Surgical Protocol The surgical protocol for patients undergoing robotic surgery has been described previously. 9 Following groin and right neck cannulation for bypass, right thoracic access ports were fashioned. Once the patient was placed on cardiopulmonary bypass at a flow of 2.4 L min 1 ms 2, a nonabsorbable polypropylene suture (Prolene; Ethicon Inc, Somerville, NJ) with a felt pledget was placed in the ascending aorta just below the right pulmonary artery. A long tack vent cannula (Medtronic, Minneapolis, MN) was fed through the chest wall in a retrograde fashion, the needle was then inserted into the cannula, and the robotic instruments were used to guide the cannula into the ascending aorta. The transthoracic clamp was inserted through the chest wall at the apex of the right axilla, and the heart was arrested with 1 L of cold blood cardioplegia, which was readministered at 20-minute intervals throughout the cross-clamp time. Cardioplegia instillation into the coronary ostia was confirmed by using transesophageal echocardiogram. On entering the left atrium and performing valve assessment, findings were summarized and the valve repair strategy was established. Patients who were deemed to require only single-scallop posterior leaflet correction, in the absence of severe myxomatous involvement at the time of robotic repair, were classified as having simple disease complexity as suggested in the 2014 AHA/ACC Heart Valve Guidelines: when leaflet dysfunction is sufficiently limited so that only annuloplasty and repair of the posterior leaflet are necessary, repair of isolated degenerative mitral disease has led to outcomes distinctly superior 10 All others, including those who required resection of >1 posterior leaflet scallop, those with severe myxomatous degeneration as judged by the operative surgeon, or those who required Neochord placement to the anterior mitral valve leaflet were classified as having complex disease again, as detailed in the 2014 AHA/ACC Guidelines: Degenerative mitral valve disease consisting of more than posterior leaflet disease requires a more complex and extensive repair. Standard published 8 robotic repair techniques were used in all cases. Our approach to mitral valve repair is tailored to patient mitral valve prolapse anatomy and the location of regurgitant lesions. In brief, in general, standard triangular resection with 2-layer polypropylene reconstruction was used for posterior leaflet disease (Figure 1A, i iv), whereas anterior leaflet prolapse was corrected by using polytetrafluoroethylene (Gore-Tex; W. L. Gore & Associates, Inc, Flagstaff, AZ) Neochord resuspension. All repairs were protected by using a standard-length posterior annuloplasty band as previously described for all open repairs at our institution. Bileaflet repair was performed by using a combination of these techniques (Figure 1B, i iv) plus annuloplasty. Adjunct techniques to repair commissural prolapse included plication (Figure 1C, i and ii) and closure of clefts (or deep indentations) associated with a regurgitant lesion (Figure 1C, iii and iv) with or without the use of pledgets as dictated by valve tissue quality. Figure 1. Contemporary mitral valve repair techniques. Simple single-scallop posterior leaflet disease (A-i) is repaired with posterior mitral leaflet triangular resection (A-ii), 2-layer Prolene reconstruction (A-iii), and flexible 63-mm posterior annuloplasty band (A-iv). Complex multiscallop posterior leaflet disease with or without severe myxomatous degeneration and anterior leaflet involvement (B-i) is typically corrected by using an array of techniques including (for example) posterior leaflet resection (B-ii), placement of Gore-Tex Neochords (B-iii), and 63-mm annuloplasty (B-iv). Adjunctive repair techniques used during both simple and complex disease included commissuroplasty (C, i and ii) and cleft closure (C, iii and iv).

3 Suri et al Midterm Outcomes Robotic Mitral Repair 1963 Table 1. Patient Characteristics Complex (n=198) Simple (n=289) Total (n=487) P Value Sex < Male, n (%) 12 (63.1) 235 (81.3) 360 (73.9) Age, y, mean (SD) 53.9 (12.1) 56.7 (10.1) 55.6 (11.0) Diabetes mellitus, n (%) 4 (2.0) 7 (2.4) 11 (2.3) Cigarette smoker, n (%) 8 (4.0) 14 (4.8) 22 (4.5) Hypertension, n (%) 64 (32.3) 118 (40.8) 182 (37.4) Chronic lung disease, n (%) 6 (3.0) 10 (3.5) 16 (3.3) Cerebrovascular disease, n (%) 4 (2.0) 3 (1.0) 7 (1.4) Previous MI, n (%) 0 (0) 3 (1.0) 3 (0.6) NYHA, n (%) I & II 186 (93.9) 276 (95.5) 462 (94.9) III & IV 12 (6.1) 13 (4.5) 25 (5.1) Congestive heart failure, n (%) 5 (2.5) 7 (2.4) 12 (2.5) Atrial fibrillation, n (%) 20 (10.1) 23 (8.0) 43 (8.8) Number diseased coronary vessels, n (%) Single vessel 5 (2.5) 17 (5.9) 22 (4.5) Two vessel 0 (0.0) 4 (1.4) 4 (0.8) Echocardiographic variables Prolapse category, n (%) < Posterior only 18 (9.1) 264 (91.3) 282 (57.9) Anterior only 17 (8.6) 2 (0.7) 19 (3.9) Bileaflet 163 (82.3) 23 (8.0) 186 (38.2) Mitral regurgitation grade, n (%) Moderate to severe 47 (23.7) 42 (14.5) 89 (18.3) Severe 151 (76.3) 247 (85.5) 398 (81.7) Mitral regurgitant volume, n (%) ml 48 (26.4) 90 (34.9) 138 (31.4) <90 ml 134 (73.6) 168 (65.1) 301 (68.6) Mitral regurgitant volume, ml, median (IQR) 73 (61 90) 79 (64 102) 76 (63 96) Ejection fraction, mean (SD) 64.6 (6.1) 64.9 (6.4) 64.8 (6.3) LVEDD, mm, mean (SD) 58.4 (5.4) 57.8 (5.3) 58.0 (5.3) LVESD, mm, mean (SD) 35.6 (4.4) 35.5 (4.3) 35.6 (4.3) LAVI, ml/m 2, mean (SD) 57.6 (17.4) 55.4 (18.4) 56.3 (18.0) PA systolic pressure, mm Hg, mean (SD) 29.3 (8.5) 32.4 (10.1) 31.1 (9.6) Tricuspid regurgitation, n (%) None, trivial, mild 181 (91.4) 270 (93.8) 451 (92.8) Moderate 17 (8.6) 18 (6.3) 35 (7.2) IQR indicates interquartile range; LAVI, left atrium volume index; LVEDD, left ventricular end-diastolic diameter; LVESD, left ventricular end-systolic diameter; MI, myocardial infarction; NYHA, New York Heart Association; PA, pulmonary artery; and SD, standard deviation. Most patients were extubated in the operating room before transfer to the intensive care unit. Patients were frequently released to a step-down unit by the evening of surgery. After hospital dismissal, all patients undergoing robotic surgery were asked to participate in protocolized clinical and echocardiographic follow-up at 1 month, 1 year, and yearly following surgery. Statistical Methods Descriptive statistics for categorical variables are reported as frequency and percentage, whereas continuous variables are reported as mean (standard deviation) or median (first and third quartiles) as appropriate. Categorical variables were compared between complex and simple cases by using the χ 2 test, and continuous variables were compared by using the 2-sample t test or Wilcoxon rank sum test where appropriate. The Kaplan-Meier method was used to construct cumulative risk curves for reoperation and calculate freedom from reoperation at different time points. Cox regression models were used to find the univariate association between repair complexity and reoperation, and MR recurrence, as well. All statistical tests were 2-sided with the α-level set at 0.05 for statistical significance. Statement of Responsibility The authors had full access to the data and take responsibility for its integrity. All authors have read and agree to the article as written.

4 1964 Circulation November 24, 2015 Table 2. Operative Data: Clinical/Echocardiographic Complex (n=198) Simple (n=289) Total (n=487) P Value Leaflet resection, n (%) 154 (77.8) 276 (95.5) 430 (88.3) < Plication, n (%) 28 (14.1) 11 (3.8) 39 (8.0) < Commissuroplasty, n (%) 105 (52.5) 43 (15.0) 148 (30.4) < Gore-Tex Neochord, n (%) 107 (54.0) 3 (1.0) 111 (22.6) < Annuloplasty, n (%) 198 (100.0) 289 (100.0) 487 (100.0) Patent foramen ovale closure, n (%) 32 (16.2) 36 (12.5) 68 (14.0) Cryoablation maze, n (%) 13 (6.6) 16 (5.5) 29 (5.9) Left atrial appendage ligation, n (%) 12 (6.1) 17 (5.7) 29 (5.9) Cross-clamp time, min, median (IQR) 58 (49 72) 50 (43 62) 53 (45 66) < Perfusion time, min, median (IQR) 81.0 ( ) 74.0 ( ) 76.0 ( ) Postoperative ventilation, h, median (IQR) 0 (0 0) 0 (0 0) 0 (0 0) Postoperative ICU stay, h, median (IQR) 8.0 ( ) 8 ( ) 8.0 ( ) Blood bank RBC requirement 2U, median (IQR) 0.0 ( ) 0.0 ( ) 0.0 ( ) Dismissal echocardiogram MR grade at dismissal None to trivial, n (%) 177 (89.8) 259 (89.6) 436 (89.7) Mild, n (%) 20 (10.2) 30 (10.4) 50 (10.3) EF, mean (SD) 55.7 (7.9) 56.0 (7.7) 55.9 (7.8) LAVI, ml/m 2, mean (SD) 44.6 (13.7) 42.3 (11.1) 43.1 (12.1) LVEDD, mm, mean (SD) 51.9 (6.2) 51.8 (5.1) 51.8 (5.6) LVESD, mm, mean (SD) 35.6 (5.8) 35.6 (5.2) 35.6 (5.5) EF indicates ejection fraction; ICU, intensive care unit; IQR, interquartile range; LAVI, left atrium volume index; LVEDD, left ventricular end-diastolic diameter; LVESD, left ventricular end-systolic diameter; MR, mitral regurgitation; RBC, red blood cell; and SD, standard deviation. Results Baseline Characteristics Baseline characteristics are shown in Table 1. All patients had significant mitral regurgitation, and in 138 (31.4%) the regurgitant volume was >90 ml per beat. There were 360 (73.9%) men, and the mean age was 55.6 years. Eleven (2.3%) were diabetic, 182 (37.4%) had hypertension, and 16 (3.3%) had chronic lung disease. Most patients were asymptomatic, 462 (94.9%) had New York heart Association class I or II symptoms, whereas only 12 (1.5%) had congestive heart failure, 43 (8.8%) had atrial fibrillation, and 451(92.8%) had noneto-mild functional secondary tricuspid regurgitation. Left ventricular ejection fraction overall was normal/hyperdynamic with a mean value of 64.8%, and left ventricular endsystolic dimension was 35.6 mm. The majority of patients, 282 (57.9%), had posterior leaflet prolapse alone, whereas 186 (38.2%) had disease of both leaflets. Regarding the posterior leaflet, the lateral scallop was involved in 17%, the middle scallop in 90%, and the medial scallop in 20%. The lateral scallop of the anterior mitral leaflet was involved in 3%, the middle scallop in 38%, and the medial scallop in 6%. Perioperative Outcomes Operative techniques are listed in Table 2 and summarized in Figure 1. The lateral scallop of the anterior leaflet was addressed in 4%, the middle scallop in 22%, and the medial scallop in 7%. In addition, the lateral scallop of the posterior leaflet was addressed in 15%, the middle scallop in 91%, and the medial scallop in 18%. Commissuroplasty was performed anterolaterally in 8%, posteromedially in 15%, and in both commissures in 8%. Standard-size posterior band annuloplasty was inserted in all cases. There were no conversions to open sternotomy, and all patients underwent successful mitral valve repair without the need for valve replacement. The overall median cross-clamp time was 53 minutes, and perfusion time was 76 minutes. Only 37 (18.7%) patients were not extubated in the operating room, and all others were taken to the intensive care unit without an endotracheal tube in place. Median length of hospital stay was 3 days. There was 1 early death (0.2; 95% confidence interval [CI], 0.01% 1.1%) in a patient who underwent hemorrhagic transformation of a chronic cerebral lesion. A neurological event occurred in 4 (0.8; 95% CI, 0.2% 2.1%) patients, and 22 of 487 (5; 95% CI, 3% 7%) required a 2 U blood transfusion. Predismissal echocardiograms demonstrated an overall mean ejection fraction of 55.9%, and 436 (89.7%) patients had none to trivial residual mitral regurgitation. Single-scallop posterior leaflet correction was performed at operation in 289 of 487 (59%) patients simple disease. During simple robotic repair, resection was performed in 276 of 289 (96%) patients, commissuroplasty in 44 of 289 (15%), and plication in 11 of 289 (4%). Patients undergoing simple repair were less likely to undergo commissuroplasty and had shorter cross-clamp and perfusion times (Table 2). Complex anatomy (multiscallop posterior leaflet, severe myxomatous disease, or anterior leaflet involvement) was addressed in 198 of 487 (41%) patients. Patients undergoing

5 Suri et al Midterm Outcomes Robotic Mitral Repair 1965 complex repair were more likely to be younger, female, with slightly lower MR volume burdens than patients with simple disease (Table 1). These patients underwent valve correction with the use of resection in 154 of 198 (78%), anterior leaflet Gore-Tex Neochords in 107 of 198 (54%), and plication in 28 of 198 (14%). Aortic cross-clamp and perfusion times were slightly longer than in those with simple disease. There were no significant differences in early postsurgical outcomes between complexity groups (Table 2). Midterm Outcomes Median clinical and echocardiographic follow-up was 381 days and 362 days, respectively (98.8% complete). New York Heart Association functional class I/II status at follow-up was documented in 97.9% (477/487) of patients. Four patients died during follow-up, 1 early and 3 following dismissal (1 complex, 3 simple), with an overall 1-year survival rate of 99.5% (99.4% simple; 99.5% complex) and an overall 5-year survival rate of 99.5% (99.4% simple; 99.5% complex, P=0.51; hazard ratio [HR], 0.48; 95% CI, ; Figure 2A). Eight patients had recurrence of moderate or greater MR (4 complex, 4 simple), with an overall 1-year freedom from MR of 99.4% (99.4% simple; 99.3% complex) and a 5-year freedom from MR of 94.6% (96.2% simple; 92.7%, complex, P=0.67; HR, 1.36; 95% CI, ; Figure 2B). There were no significant differences in MR recurrence, ejection fraction, left ventricular chamber size, or residual MR grade between those with simple versus complex disease pathology (Table 3). Seven patients (5 complex, 2 simple) underwent mitral reoperation, with an overall 1-year freedom from reoperation of 98.8% (100% simple; 97.2% complex), and a 5-year freedom from reoperation of 97.7% (99.2% simple and 95.7% complex, P=0.13; HR, 3.35; 95% CI, ; Figure 2C). In 5 patients, the reason for reoperation was MR recurrence, whereas 1 patient had endocarditis and 1 required surgical removal of left atrial thrombus. Predictors of Survival, Regurgitation Recurrence, and Reoperation Because there were only a limited number of events, we were unable to ascertain the predictors of survival, MR recurrence, or reoperation. Discussion This report from a large tertiary referral center details the midterm clinical and echocardiographic outcomes of 487 patients undergoing robotic repair of degenerative mitral valve disease in accordance with class IIa ACC/AHA Guideline recommendations, with follow-up that is 98% complete. The results reflect a 100% repair rate with 0.2% early mortality and 0.8% stroke risks, translating into excellent 5-year survival and very low likelihoods of MR recurrence or reoperation. The complexity of technical repair did not appear to influence MR recurrence or mitral valve reoperation risks. Together, these results support for the first time that a minimally invasive approach is capable of meeting quality mandates set forth in expert consensus statements detailing recommended management of stage C1 patients undergoing early correction of severe degenerative MR. 2 A B Survival (%) Moderate or greater mitral regurgitation (%) C Mitral reoperation (%) P=0.51 Complexity 20 Simple repair Complex repair Follow-up time (year) Complexity Simple repair Complex repair P= Follow-up time (year) Complexity Simple repair Complex repair Follow-up time (year) P= Figure 2. Kaplan-Meier curves detailing midterm quality outcome end points stratified by disease complexity: A, Overall survival. B, Recurrence of mitral regurgitation (moderate or greater). C, Mitral reoperation. Comparison With the Benchmark: Open Mitral Repair Recent landmark open mitral repair outcomes published by David et al 11 detailed long-term outcomes of 840 patients undergoing mitral valve repair for MR attributable to degenerative disease with 10.4-year median follow-up. Freedom from recurrent moderate or severe MR at 20 years was 69.2%. Repair failure was predicted by age, anterior leaflet prolapse, extent of myxomatous disease, lack of mitral annuloplasty, and duration of cardiopulmonary bypass. The risk of mitral reoperation was 5.9%. Our current series demonstrates that MR recurrence after robotic mitral valve repair is also very low, with an overall 1-year cumulative probability of 0.67% (0.41% simple; 1% complex) and a 5-year cumulative probability of 4% (1.9% simple; 6.6% complex; HR, 2.33; 95% CI, ; P=0.18). Uniquely, we strongly advised patients to return for protocolized clinical and echocardiographic follow-up

6 1966 Circulation November 24, 2015 Table 3. Midterm Follow-Up Complex (n=198) Simple (n=289) Total (n=487) P Value One year MR grade, n (%) None trivial 89 (87.1) 107 (75.9) 196 (78.4) Mild 18 (16.5) 31 (22.0) 49 (19.6) Moderate 1 (0.9) 3 (2.1) 4 (1.6) >Moderate 1 (0.9) 0 (0.0) 1 (0.4) EF, mean (SD) 57.8 (7.2) 58.8 (6.8) 58.4 (7.0) LAVI, ml/m 2, mean (SD) 34.2 (10.8) 32.1 (7.4) 33.0 (9.0) LVEDD, mm, mean (SD) 49.8 (5.2) 49.3 (4.5) 49.5 (4.8) LVESD, mean (SD) 33.7 (5.3) 32.9 (4.5) 33.3 (4.9) NYHA, n (%) I & II 123 (100.0) 175 (99.4) 297 (99.7) III & IV 0 (0.0) 1 (0.6) 1 (0.3) >1 y EF, mean (SD) 60.5 (6.7) 60.0 (6.2) 60.2 (6.4) MR grade, n (%) None to trivial 43 (74.1) 60 (74.1) 103 (74.1) Mild 12 (20.7) 16 (19.8) 28 (20.1) Moderate 2 (3.4) 3 (3.7) 5 (3.6) > Moderate 1 (1.7) 2 (2.5) 3 (2.2) LAVI, ml/m 2, mean (SD) 36.7 (12.8) 32.5 (8.4) 34.3 (10.7) LVEDD, mean (SD) 49.2 (4.6) 49.0 (4.4) 49.1 (4.4) LVESD, mean (SD) 32.4 (4.6) 32.1 (4.4) 32.3 (4.4) EF indicates ejection fraction; LAVI, left atrium volume index; LVEDD, left ventricular end-diastolic diameter; LVESD, left ventricular end-systolic diameter; MR, mitral regurgitation; NYHA, New York Heart Association; and SD, standard deviation. performed at routine intervals following robotic repair, which has never been undertaken to date in prior minimally invasive repair experiences in the literature. Through intensive protocolized follow-up, we found that the risk of mitral reoperation was very low, with a 1-year cumulative probability of 1.2% (0% simple; 2.8% complex) and 5-year cumulative incidence of mitral reoperation of 2.3% (0.9% simple; 4.3% complex; HR, 3.25; 95% CI, ; P=0.16). Together, the currently reported results are comparable to those attained by master repair surgeons performing high volumes of open mitral valve repair and also fulfill quality criteria imperatives of the current ACC/AHA heart valve guidelines. 2 Robotic Mitral Repair: the Knowledge Gap The lack of midterm quality data following robotic mitral valve repair has contributed to suboptimal understanding of natural history and outcomes following intervention. This is in large part because, once patients undergo successful correction of MR, they often return to normal daily lives without functional limitation and thus lose the incentive to undergo routine clinical or echocardiographic assessments. Indeed, our data show that 98% of our patients reported New York Heart Association I/II functional status during midterm follow-up after robotic mitral valve repair. Finally, there are also few consensus-based recommendations for postrepair clinical or echocardiographic follow-up after successful degenerative MR correction. One of the first mid-term experiences of robotic repair was reported by Yoo and colleagues 12 from Asan Medical Center studying 200 patients who underwent operations between August 2007 and December Echocardiographic follow-up (>6 months) was available in 187 patients (93.5%) at a median of 29.6 months (interquartile range, months). Freedom from moderate or greater mitral regurgitation at 5 years was only reported to be 87.0±2.6% however. Our current results suggest that contemporary freedom from recurrent MR is substantially greater than this in the current era using advanced repair techniques. When specifically considering the performance of complex mitral repair in patients with anterior and bileaflet mitral valve prolapse subsets, very little additional evidence also exists. Rodriguez and coworkers studied 66 patients, 14 with anterior leaflet disease and 52 with bileaflet prolapse. During a mean follow-up of 795±495 days, recurrent regurgitation was moderate in 2 (3.3%) and severe in 4 (6.7%), whereas 6 (9%) patients required mitral reoperation. The current results we present once again suggest that quality has continued to improve since the publication of these early reports, and thus reappraisal is warranted. The new understanding of very low MR recurrence risk following robotic repair detailed in our present report (1- and 5-year cumulative probability of MR recurrence of 0.6% and 5.4%) is critically important to inform the decisions of heart teams and patients during the

7 Suri et al Midterm Outcomes Robotic Mitral Repair 1967 consideration of therapeutic alternatives in treating degenerative MR. Percutaneous Mitral Repair: the Indication Gap The least invasive therapy available is often the most attractive to asymptomatic patients, who prior to echocardiographic diagnosis, were otherwise unaware of their disease state. Percutaneous correction using the MitraClip (Abbott Vascular) device has been approved by regulatory bodies in the United States for use in high-risk symptomatic patients with degenerative MR and is increasingly considered an alternative to traditional surgery to diminish, but not eliminate MR burden. 13 As reported in the Endovascular Valve Edge-to-Edge Repair Study (EVEREST) II trial, at 12 months and 4 years, the proportions of patients with 3+ or 4+ MR following percutaneous repair (including those with anterior leaflet involvement) were 18.8% (28/149) and 20.6% (20/97), respectively. 5 Specific analysis of degenerative MR patients revealed that 14.7% (10/68) had moderate or greater MR 1 year following MitraClip repair. By comparison, the risk of recurrent MR in the current report after robotic repair in patients with very low risk is extremely favorable (0.6%). It is thus essential that providers and patients interested in less invasive contemporary alternatives to conventional open chest surgery be informed of these outcomes. Importantly, MitraClip therapy is capable of at least diminishing MR burden in patients deemed unsuitable for any type of surgery, and thus will likely continue to play an important role in high-risk patient populations for the foreseeable future. New Messages In order for consensus statements to improve the prognosis of stage C1 patients with severe degenerative MR undergoing surgical correction in accordance with class IIa recommendations, several a priori criteria must be met. 2 First, mitral valve repair must be offered with a very high likelihood (>95%). Second, these operations must be performed with extremely low mortality and morbidity risk (<1%). Third, repair must be durable with a <1% per year reoperation risk. The current report conveys several important messages that both differentiate it from previous series and meet these mandates. First, our findings demonstrate a 100% repair rate, a <0.2% mortality risk, and excellent restoration of normal functional class, providing a novel and heretofore absent contemporary comparator against which forthcoming percutaneous technologies must be assessed. Second, although the early results of robotic mitral valve repair have been reported previously, 8,14 16 midterm quality outcomes obtained through uniform assessments have also been lacking. We present the most recent clinical and echocardiographic evaluations of repair stability through multiple points of contact for each patient over time, which provides a better understanding of the true quality outcomes of robotic mitral valve repair. Third, current heart valve guidelines indicate that patients undergoing simple repair should have a >80% freedom from recurrent moderate or severe ( 3+) MR at 15 to 20 years after operation 2 thus indicating that the 5-year 3.8% risk of MR recurrence in patients undergoing simple robotic repair seen in our study easily attains benchmark quality criteria. Fourth, whereas the ACC/AHA Guidelines suggest that more complex repair is not well standardized with a freedom from reoperation of approximately 80% at 15 to 20 years, 2 the 5-year cumulative probability of reoperation among complex disease subsets of 4.3% that we currently report is, again, well within established quality requirements. Fifth, these data now represent an important comparator to facilitate informed decision making among heart teams and patients with severe degenerative MR. 17 Understanding that robotic repair is currently available at certain centers of excellence with near-absolute certainty, very low procedural risks and excellent durability are absolutely critical variables when considering therapeutic options for patients with stage C1 MR. It is important to acknowledge that the aforementioned tenets underpinning the quality of robotic repair may not routinely be assured outside certain heart valve repair centers of excellence, thus tempering widespread enthusiasm for early referral. Finally, ongoing longitudinal clinical and echocardiographic assessments following both minimally invasive and percutaneous mitral repair will be essential to ascertain durability in comparison with the known results of open operations. Limitations This study was subject to the limitations inherent in a nonrandomized observational series. Patients in this study were necessarily selected because of their willingness and availability to undergo clinical and echocardiographic surveillance. We were unable to obtain follow-up echocardiograms in each and every patient of our population despite several attempts to contact them. We have no reason to believe, however, that such patients were lost to follow-up in a nonrandom fashion. Finally, the very long-term outcomes of less invasive are unavailable and, until appropriate follow-up can be accrued, midterm results should be interpreted accordingly. Conclusion Midterm quality outcomes after robotic mitral repair are excellent regardless of mitral valve repair complexity, including a very high survival, infrequent complications, and a very low likelihood of MR recurrence. Robotic mitral valve repair provides definitive correction of severe degenerative MR and should be considered in asymptomatic patients with preserved left ventricular function according to class IIa Guideline recommendations. These latest results should be used to inform the decisions of patients, along with referring providers, and must also serve as a compelling comparator to rapidly disseminating percutaneous approaches. None. Disclosures References 1. Kang DH, Park SJ, Sun BJ, Cho EJ, Kim DH, Yun SC, Song JM, Park SW, Chung CH, Song JK, Lee JW, Park PW. Early surgery versus conventional treatment for asymptomatic severe mitral regurgitation: a propensity analysis. J Am Coll Cardiol. 2014;10: a. Suri RM, Vanoverschelde JL, Grigioni F, Schaff HV, Tribouilloy C, Avierinos JF, Barbieri A, Pasquet A, Huebner M, Rusinaru D, Russo A, Michelena HI, Enriquez-Sarano M. Association between early surgical intervention vs watchful waiting and outcomes for mitral regurgitation due to flail mitral valve leaflets. JAMA. 2013;310: doi: /jama Nishimura RA, Otto CM, Bonow RO, Carabello BA, Erwin JP 3rd, Guyton RA, O Gara PT, Ruiz CE, Skubas NJ, Sorajja P, Sundt TM 3rd, Thomas JD; American College of Cardiology/American Heart Association Task

8 1968 Circulation November 24, 2015 Force on Practice Guidelines AHA/ACC guideline for the management of patients with valvular heart disease: executive summary: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. Circulation. 2014;129: doi: /CIR Castillo JG, Anyanwu AC, Fuster V, Adams DH. A near 100% repair rate for mitral valve prolapse is achievable in a reference center: implications for future guidelines. J Thorac Cardiovasc Surg. 2012;144: doi: /j.jtcvs David TE, Armstrong S, Ivanov J. Chordal replacement with polytetrafluoroethylene sutures for mitral valve repair: a 25-year experience. J Thorac Cardiovasc Surg. 2013;145: doi: /j.jtcvs Glower DD, Kar S, Trento A, Lim DS, Bajwa T, Quesada R, Whitlow PL, Rinaldi MJ, Grayburn P, Mack MJ, Mauri L, McCarthy PM, Feldman T. Percutaneous mitral valve repair for mitral regurgitation in high-risk patients: results of the EVEREST II study. J Am Coll Cardiol. 2014;64: doi: /j.jacc Mihaljevic T, Jarrett CM, Gillinov AM, Williams SJ, DeVilliers PA, Stewart WJ, Svensson LG, Sabik JF 3rd, Blackstone EH. Robotic repair of posterior mitral valve prolapse versus conventional approaches: potential realized. J Thorac Cardiovasc Surg. 2011;141:72 80.e1. doi: /j.jtcvs Mihaljevic T, Koprivanac M, Kelava M, Goodman A, Jarrett C, Williams SJ, Gillinov AM, Bajwa G, Mick SL, Bonatti J, Blackstone EH. Value of robotically assisted surgery for mitral valve disease. JAMA Surg. 2014;149: doi: /jamasurg Suri RM, Burkhart HM, Daly RC, Dearani JA, Park SJ, Sundt TM 3 rd, Li Z, Enriquez-Sarano M, Schaff HV. Robotic mitral valve repair for all prolapse subsets using techniques identical to open valvuloplasty: establishing the benchmark against which percutaneous interventions should be judged. J Thorac Cardiovasc Surg. 2011;142: doi: /j.jtcvs Suri RM, Burkhart HM. Optimizing outcomes of robotic mitral valve repair for all prolapse anatomy: the Suri-Burkhart technique. Ann Cardiothorac Surg. 2013;2: doi: /j.issn X Nishimura RA, Otto CM, Bonow RO, Carabello BA, Erwin JP 3rd, Guyton RA, O Gara PT, Ruiz CE, Skubas NJ, Sorajja P, Sundt TM 3rd, Thomas JD; American College of Cardiology/American Heart Association Task Force on Practice Guidelines AHA/ACC guideline for the management of patients with valvular heart disease: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. Circulation. 2014;129:e521 e643. doi: / CIR David TE, Armstrong S, McCrindle BW, Manlhiot C. Late outcomes of mitral valve repair for mitral regurgitation due to degenerative disease. Circulation. 2013;127: doi: / CIRCULATIONAHA Yoo JS, Kim JB, Jung SH, Kim DH, Choo SJ, Chung CH, Lee JW. Mitral durability after robotic mitral valve repair: analysis of 200 consecutive mitral regurgitation repairs. J Thorac Cardiovasc Surg. 2014;148: doi: /j.jtcvs Minha S, Torguson R, Waksman R. Overview of the 2013 Food and Drug Administration Circulatory System Devices Panel meeting on the MitraClip Delivery System. Circulation. 2013;128: doi: /CIRCULATIONAHA Chitwood WR Jr, Rodriguez E, Chu MW, Hassan A, Ferguson TB, Vos PW, Nifong LW. Robotic mitral valve repairs in 300 patients: a singlecenter experience. J Thorac Cardiovasc Surg. 2008;136: doi: /j.jtcvs Rodriguez E, Nifong LW, Chu MW, Wood W, Vos PW, Chitwood WR. Robotic mitral valve repair for anterior leaflet and bileaflet prolapse. Ann Thorac Surg. 2008;85: ; discussion 444. doi: /j. athoracsur Rodriguez E, Randolph Chitwood W Jr. Outcomes in robotic cardiac surgery. J Robot Surg. 2007;1: doi: /s Anyanwu AC, Bridgewater B, Adams DH. The lottery of mitral valve repair surgery. Heart. 2010;96: doi: / hrt Clinical Perspective Although the repair of simple single-scallop mitral valve disease is addressed via an open chest approach at many centers around the world with known results, the midterm quality outcomes of minimally invasive repair, particularly for more complex disease are unknown. We studied the midterm clinical and echocardiographic outcomes of 487 patients undergoing robotic repair of degenerative mitral valve disease in accordance with class IIa American College of Cardiology/American Heart Association Guideline recommendations, with follow-up that was 98% complete. The results reflect a 100% repair rate with 0.2% early mortality and 0.8% stroke risks, translating into excellent 5-year survival and very low likelihoods of MR recurrence or reoperation. The complexity of technical repair did not appear to influence MR recurrence or mitral valve reoperation risks. Together, these results support for the first time that a minimally invasive approach is capable of meeting quality mandates set forth in expert consensus statements detailing recommended management of stage C1 patients undergoing early correction of severe degenerative MR.