Faculty Bibliography

OBJECTIVE: Current video-assisted thoracoscopic surgery training models rely on animals or mannequins to teach procedural skills. These approaches lack inherent teaching/testing capability and are limited by cost, anatomic variations, and single use. In response, we hypothesized that video-assisted thoracoscopic surgery right upper lobe resection could be simulated in a virtual reality environment with commercial software. METHODS: An anatomy explorer (Maya [Autodesk Inc, San Rafael, Calif] models of the chest and hilar structures) and simulation engine were adapted. Design goals included freedom of port placement, incorporation of well-known anatomic variants, teaching and testing modes, haptic feedback for the dissection, ability to perform the anatomic divisions, and a portable platform. RESULTS: Preexisting commercial models did not provide sufficient surgical detail, and extensive modeling modifications were required. Video-assisted thoracoscopic surgery right upper lobe resection simulation is initiated with a random vein and artery variation. The trainee proceeds in a teaching or testing mode. A knowledge database currently includes 13 anatomic identifications and 20 high-yield lung cancer learning points. The 'patient' is presented in the left lateral decubitus position. After initial camera port placement, the endoscopic view is displayed and the thoracoscope is manipulated via the haptic device. The thoracoscope port can be relocated; additional ports are placed using an external 'operating room' view. Unrestricted endoscopic exploration of the thorax is allowed. An endo-dissector tool allows for hilar dissection, and a virtual stapling device divides structures. The trainee's performance is reported. CONCLUSIONS: A virtual reality cognitive task simulation can overcome the deficiencies of existing training models. Performance scoring is being validated as we assess this simulator for cognitive and technical surgical education

OBJECTIVE: Functional ischemic mitral regurgitation is a complication of ventricular remodeling; standard therapy is reduction annuloplasty and coronary artery bypass grafting. Unfortunately, outcomes are retrospective and contradictory. We report a multicenter study that documents the outcomes of reduction annuloplasty for functional ischemic mitral regurgitation. METHODS: Twenty-one centers randomized 75 patients to the coronary artery bypass grafting + reduction annuloplasty subgroup that was the control arm of the Randomized Evaluation of a Surgical Treatment for Off-pump Repair of the Mitral Valve trial. Entry criteria included patients requiring revascularization, patients with severe or symptomatic moderate functional ischemic mitral regurgitation, an ejection fraction 25% or greater, a left ventricular end-diastolic dimension 7.0 cm or less, and more than 30 days since acute myocardial infarction. All echocardiograms were independently scored by a core laboratory. Reduction annuloplasty was achieved by device annuloplasty. Two patients underwent immediate intraoperative conversion to a valve replacement because reduction annuloplasty was unable to correct mitral regurgitation; as-treated results are presented. RESULTS: Thirty-day mortality was 4.1% (3/73). Patients received an average of 2.8 bypass grafts. Mean follow-up was 24.6 months. Mitral regurgitation was reduced from 2.6 +/- 0.8 preoperatively to 0.3 +/- 0.6 at 2 years. Freedom from death or valve reoperation was 78% +/- 5% at 2 years. There was significant improvement in ejection fraction and New York Heart Association class with reduction of left ventricular end-diastolic dimension. Cox regression analyses suggested that increasing age (P = .001; hazard ratio, 1.16 per year; 95% confidence interval, 1.06-1.26) and renal disease (P = .018; hazard ratio, 3.48; 95% confidence interval, 1.25-9.72) were associated with decreased survival. CONCLUSIONS: Coronary artery bypass grafting + reduction annuloplasty for functional ischemic mitral regurgitation predictably reduces mitral regurgitation and relieves symptoms. This treatment of moderate to severe mitral regurgitation is associated with improved indices of ventricular function, improved New York Heart Association class, and excellent freedom from recurrent mitral insufficiency. Although long-term prognosis remains guarded, this multicenter study delineates the intermediate-term benefits of such an approach

Evaluation of: Chikwe J, Goldstone AB, Passage J et al.: A propensity score-adjusted retrospective comparison of early- and mid-term results of mitral-valve repair versus replacement in octogenarians. Eur. Heart J. 32(5), 618-626 (2011). Mitral regurgitation (MR) is common in the elderly, increasing in prevalence with age. Common causes of MR include: degenerative disease of the valve and subvalvular apparatus; ischemic MR due to annular dilatation, papillary muscle displacement and left ventricular remodeling; rheumatic mitral valve disease and infectious endocarditis. The optimal treatment of severe mitral insufficiency in the elderly remains unknown. Mitral-valve repair or replacement have historically been considered high risk in older patients and, for this reason, many elderly patients are not offered surgery. Yet with recent advances in surgical techniques and outcomes, mitral-valve surgery is being increasingly utilized in elderly patients. A recent study by Chikwe et al. in the European Heart Journal examines overall and comparative outcomes of mitral-valve repair and mitral-valve replacement in an elderly cohort. This study finds that mitral-valve repair confers a survival benefit relative to mitral-valve replacement in octogenarians, particularly in patients undergoing surgery for degenerative disease. 2011 Future Medicine Ltd

OBJECTIVES: We sought to determine whether patients with functional mitral regurgitation (FMR) would benefit from ventricular reshaping by the Coapsys device (Myocor, Inc., Maple Grove, Minnesota). BACKGROUND: FMR occurs when ventricular remodeling impairs valve function. Coapsys is a ventricular shape change device placed without cardiopulmonary bypass to reduce FMR. It compresses the mitral annulus and reshapes the ventricle. We hypothesized that Coapsys for FMR would improve clinical outcomes compared with standard therapies. METHODS: RESTOR-MV (Randomized Evaluation of a Surgical Treatment for Off-Pump Repair of the Mitral Valve) was a randomized, prospective, multicenter study of patients with FMR and coronary disease with core laboratory analysis. After enrollment, patients were stratified to the standard indicated surgery: either coronary artery bypass graft alone or coronary artery bypass graft with mitral valve repair. In each stratum, randomization was to either control (indicated surgery) or treatment (coronary artery bypass graft with Coapsys ventricular reshaping). RESULTS: The study was terminated when the sponsor failed to secure ongoing funding; 165 patients were randomized. Control and Coapsys both produced decreases in left ventricular (LV) end-diastolic dimension and MR at 2 years (p < 0.001); Coapsys provided a greater decrease in LV end-diastolic dimension (p = 0.021). Control had lower MR grades during follow-up (p = 0.01). Coapsys showed a survival advantage compared with control at 2 years (87% vs. 77%) (hazard ratio: 0.421; 95% confidence interval: 0.200 to 0.886; stratified log-rank test; p = 0.038). Complication-free survival (including death, stroke, myocardial infarction, and valve reoperation) was significantly greater with Coapsys at 2 years (85% vs. 71%) (hazard ratio: 0.372; 95% confidence interval: 0.185 to 0.749; adjusted log-rank test; p = 0.019). CONCLUSIONS: Analysis of RESTOR-MV indicates that patients with FMR requiring revascularization treated with ventricular reshaping rather than standard surgery had improved survival and a significant decrease in major adverse outcomes. This trial validates the concept of the ventricular reshaping strategy in this subset of patients with heart failure. (Randomized Evaluation of a Surgical Treatment for Off-Pump Repair of the Mitral Valve [RESTOR-MV]; NCT00120276)

BACKGROUND: Elderly patients requiring reoperative cardiac surgery for valve disease are considered high risk for immediate outcomes, but little is known about their long-term survival. It is often conjectured that medical therapy provides equivalent late survival in this population, which may dissuade both patient and surgeon from considering reoperation. We analyzed a cohort of such patients undergoing reoperative valve surgery to determine their long-term survival. METHODS: From 1992 through 2007, 363 patients aged 75 years or more underwent reoperative isolated valve surgery; 211 (58%) had aortic valve replacement and 152 (42%) had mitral valve surgery. Mean age was 80.5 years. Hospital outcomes were prospectively recorded. Survival from all-cause death was determined from the Social Security Death Index. RESULTS: Hospital mortality was 13.8% (12.8% for aortic and 15.1% for mitral valve operations; p = 0.52). Multivariable predictors of hospital death were New York Heart Association functional class III or IV heart failure (odds ratio = 3.19, p = 0.012), dialysis (odds ratio = 15.63, p = 0.003), and more than one reoperation (odds ratio = 2.59, p = 0.058). At 5 years, overall survival was 62% +/- 3% for all patients (66% +/- 4% for aortic and 56% +/- 4% for mitral valve patients). For aortic valve patients aged 80 years or more, 5-year survival was 60% +/- 0.6%. Life expectancy table analysis predicted a 5-year survival of 57% for an age-matched and sex-matched comparison group. CONCLUSIONS: Reoperative surgery for elderly patients with isolated aortic or mitral valve pathology is associated with excellent long-term survival, particularly when treating aortic valve disease. While in-hospital mortality is higher among the elderly than among younger patients, specific predictors of poor outcome can be identified preoperatively to risk stratify these patients

A 60-year-old man presented with symptoms from an intracardiac mass. His medical history included retroperitoneal fibrosis (Ormond disease). Magnetic resonance imaging revealed an obstructing bilobular mass in the right atrium, located at the caval junction and extending intramurally into the atria, septum, and right ventricle. En bloc resection of the right atrium, interatrial septum, dome of the left atrium, vena cava, anterior tricuspid annulus, right coronary artery, and partial right ventriculectomy was completed with right ventricular repair, tricuspid valve replacement, and left and right atrial replacement with bovine pericardium. This lesion was a myofibroblastic tumor with the same histologic features as his retroperitoneal fibrosis

BACKGROUND: Functional mitral regurgitation (FMR) is associated with leaflet displacement and tethering. Little is known about regional coaptation zones, including variations in coaptation length (CL) and contributions of anterior and posterior leaflets. Regional coaptation zones were analyzed in patients with normal mitral valves and with FMR. METHODS: Cardiac surgery patients underwent a three-dimensional transesophageal echocardiography. Four-dimensional volumetric datasets were acquired with Doppler interrogation. Offline analysis was performed. Orthogonal views were extracted in diastole and systole. Leaflet dimensions and coaptation distance and depth were examined for posterior and apical displacement of the coaptation zones. RESULTS: Twenty patients were analyzed (10 normal and 10 with 2 to 4+ FMR). Anterior leaflet CL was greater than posterior leaflet CL: 2.2+/-0.6 mm versus 0.9+/-0.3 mm in region 1, 3.2+/-0.7 mm versus 1.2+/-0.6 mm in region 2, and 1.8+/-0.4 mm versus 0.6+/-0.3 mm in region 3 (p<0.001). The FMR was associated with shorter leaflet CLs, with a mean anterior CL of 1.7+/-0.4 mm versus 3.1+/-0.4 mm (p=0.04), and a mean posterior CL of 0.7+/-0.3 mm versus 1.1+/-0.3 mm (p=0.03). The biggest difference in CLs was in A2-P2. Coaptation distance and depth were higher in the FMR group: 21.7+/-1.0 mm versus 17.9+/-1.0 mm (p=0.01), and 8.6+/-0.7 mm versus 5.0+/-0.7 mm (p<0.01). CONCLUSIONS: Mitral valve leaflet CL is asymmetric in normal valves, with anterior dominance. Functional mitral regurgitation is associated with a relocated coaptation zone, regional changes, and diminished coaptation. These data suggest an 'anterior leaflet reserve.' Posterior movement of the coaptation line compensates for annular dilation and presumed left ventricular enlargement in order to maintain competency until inadequate anterior leaflet CL occurs

BACKGROUND: A recent report suggested that a thoracotomy approach for reoperative mitral valve (MV) procedures was associated with an equivalent mortality and an unacceptable risk of stroke. We assessed these outcomes in a single institution's experience. METHODS: From 1992 through 2007, 905 patients underwent reoperative MV procedures. The approach was a median sternotomy in 612 (67.6%), right anterior thoracotomy in 242 (26.7%), and left posterior thoracotomy in 51 (5.6%). Concomitant procedures in 411 patients (67.6%) included aortic procedures in 189, tricuspid procedures in 170, and coronary artery bypass grafting in 90. Hypothermic fibrillation was used in 65 patients. Logistic analysis was used to analyze risk factors and outcomes. RESULTS: Overall mortality was 12.7% (115 of 905), 6.7% (25 of 371) for first time isolated MV reoperations, and 10.1% (50 of 494) for all isolated MV operations. Overall incidence of stroke was 3.8% (34 of 905); 10.9% (9 of 82) with retrograde arterial perfusion and 3.0% (25 of 824) with central aortic cannulation (p < 0.001). For isolated MV reoperations, the incidence of stroke was 4.3% (21 of 494): 2.9% (7 of 241) for antegrade perfusion and 5.5% (14 of 253) for retrograde perfusion (p = 0.15). Risk factors for death were age (p < 0.001), renal failure (p < 0.01), tricuspid valve disease (p < 0.001), chronic obstructive pulmonary disease (odds ratio [OR], 2.9; 95% confidence interval [CI], 1.8 to 4.9; p < 0.001), emergency procedure (OR, 2.9; 95% CI, 1.2 to 6.9; p = 0.02), and ejection fraction less than 0.30 (OR, 1.9; 95% CI, 1.1 to 3.3, p = 0.018). Risk factors for stroke were retrograde perfusion (OR, 4.4; 95% CI, 1.8 to 10.3; p < 0.01) and ejection fraction below 0.30 (OR, 2.1; 95% CI, 0.9 to 5.0; p = 0.09). CONCLUSIONS: The incidence of stroke in reoperative MV operations is associated with perfusion strategies, not with the incisional approach. Reoperative sternotomy and minithoracotomy with central cannulation are both useful for reoperative MV procedures and are associated with low stroke rates