Faculty Bibliography

OBJECTIVE: Systolic anterior motion (SAM) can occur after mitral valve repair (MVr), most frequently in patients with degenerative valve disease. Our initial observations (1981-1990) revealed that most patients with SAM can be successfully treated medically. Here the authors review the last 16 years of their experience with SAM after MVr. METHODS: Between January 1996 and October 2011, 1918 patients with degenerative mitral valve disease underwent MVr at our institution. We performed a retrospective analysis of SAM in this patient population. RESULTS: The incidence of SAM was 4.6% (89 of 1918) overall, 4.0% (77 of 1906) in patients who did not have SAM preoperatively (de novo). Compared with our previously published report, the incidence of SAM decreased from 6.4% to 4.0% (P = .03). Hospital mortality was 2.0% (38 of 1918) overall, 1.3% (14 of 1078) for isolated MVr. One patient with de novo SAM (1 of 77; 1.3%) died after emergency MVr. All patients with de novo SAM were successfully managed conservatively with intravenous fluids, alpha agonists, and/or beta blockers. A higher incidence of SAM was associated with a left ventricular ejection fraction greater than 60% (P = .01), posterior leaflet resection (P = .048), and hypertrophic obstructive cardiomyopathy (P < .01). The incidence of SAM was lower in patients who underwent device mitral annuloplasty with a semirigid posterior band compared with a complete ring (P = .03). CONCLUSIONS: In the more recent era, SAM occurs one-third less frequently after repair of degenerative mitral valve disease. Use of an incomplete annuloplasty band rather than a complete ring is associated with a lower incidence of SAM. The mainstay treatment of SAM continues to be medical management.

OBJECTIVE: Although the technique of totally endoscopic robotic mitral valve repair (TERMR) has been well described, few reports have examined the results of peripheral perfusion with balloon clamping. We analyzed the outcomes of TERMR performed using this strategy. METHODS: A total of 108 consecutive patients underwent TERMR by a 2-surgeon team. The preoperative evaluation included chest computed tomography and abdominal and pelvis computed tomography. Additional procedures included appendage exclusion in 96, patent foramen ovale closure in 29, cryoablation in 16, tricuspid valve repair in 2, and septal myectomy in 2. The mean patient age was 59 years (range, 21-86). Central venous drainage was obtained with a long cannula. Arterial return was achieved with femoral cannulation, when possible. An endoballoon catheter was placed through the femoral artery. Transesophageal echocardiography was used to position all catheters. RESULTS: Femoral artery perfusion was possible in 103 of 108 patients (95.3%). The subclavian artery was used in 5 patients (4.6%) with contraindications to retrograde perfusion. An endoballoon clamp was placed by way of the femoral artery. In 105 of 108 patients (97.2%), endoaortic occlusion was successfully used; the mean crossclamp time was 87.4 minutes. The coronary sinus cardioplegia catheter was placed successfully in 81 of the 108 patients (75%). Postoperatively, no or mild inotropic support was needed in 94 (87%) and moderate support in 14 (13.0%). Of the 108 patients, 55 (50.9%) were extubated in the operating room. No hospital mortality, aortic injury, vascular complications, or wound infections occurred. Complications included 2 strokes (no residual deficit) (1.8%) and atrial fibrillation in 18 (16.7%). The median hospital stay was 4 days. Eighty patients (74.1%) were discharged by postoperative day 5. CONCLUSIONS: A preoperative image-guided perfusion strategy and aortic balloon clamping permit routine TERMR with excellent myocardial preservation and minimal complications.

BACKGROUND AND AIM OF THE STUDY: Optimal repair of the mitral valve involves the implantation of an annuloplasty device to geometrically reshape and/or stabilize the annulus and improve long-term durability. It has been reported previously that trigone-to-trigone semi-rigid posterior band (PB) annuloplasty is associated with excellent short-term outcomes, physiologic motion of the anterior mitral annulus and leaflet, and lower postoperative transvalvular gradients compared to complete ring (CR) annuloplasty. The aim of this retrospective study was to compare the long-term effectiveness of PB and CR annuloplasty in patients with degenerative mitral valve regurgitation (MR). METHODS: Between 1993 and 2010, a total of 1,612 patients with degenerative MR underwent mitral valve repair (MVr) with either PB (n = 1,101) or CR (n = 511). Initially, CR was the annuloplasty device of choice, but after 2001 PB was preferred. A retrospective review of clinical and echocardiographic follow up was performed on these patients. The eight-year cumulative freedom from adverse events were determined by life-table analysis. RESULTS: Hospital mortality was 1.9% overall (n = 30/1612), but 1.3% (12/939) for isolated MVr, and 2.7% (18/673) for MVr with concomitant procedures (p = 0.04). Hospital mortality was similar for both PB (1.9%; 21/1101) and CR (1.8%; 9/511) (p = 0.8). The mean MR grade was reduced from 3.9 +/- 0.3 preoperatively to 0.6 +/- 0.9 at follow up using PB (p < 0.01), and from 3.9 +/- 0.4 to 0.9 +/- 0.9 using CR (p < 0.01). PB was associated with a similar long-term freedom from death (77 +/- 0.03% versus 83 +/- 0.02%; p = 0.4), reoperation (95 +/- 0.01% versus 92 +/- 0.01%; p = 0.06), and reoperation or recurrent severe MR (91 +/- 0.02% versus 92 +/- 0.01%; p = 0.7), and slightly greater freedom from valve-related complications compared to CR (91 +/- 0.02% versus 87 +/- 0.02%; p = 0.02). CONCLUSION: The long-term outcome of mitral valve annuloplasty with PB was comparable to that with CR for degenerative disease. Anterior annuloplasty was found to be unnecessary in this patient population.

OBJECTIVE: A concern with the initiation of totally endoscopic robotic mitral valve repair (TERMR) programs has been the risk for the learning curve. To minimize this risk, we initiated a TERMR program with a defined team and structured learning approach before clinical implementation. METHODS: A dedicated team (two surgeons, one cardiac anesthesiologist, one perfusionist, and two nurses) was trained with clinical scenarios, simulations, wet laboratories, and "expert" observation for 3 months. This team then performed a series of TERMRs of varying complexity. RESULTS: Thirty-two isolated TERMRs were performed during the first programmatic year. All operations included mitral valve repair, left atrial appendage exclusion, and annuloplasty device implantation. Additional procedures included leaflet resection, neochordae insertion, atrial ablation, and papillary muscle shortening. Longer clamp times were associated with number of neochordae (P < 0.01), papillary muscle procedures (P < 0.01), and leaflet resection (P = 0.06). Sequential case number had no impact on cross-clamp time (P = 0.3). Analysis of nonclamp time demonstrated a 71.3% learning percentage (P < 0.01; ie, 28.7% reduction in nonclamp time with each doubling of case number). There were no hospital deaths or incidences of stroke, myocardial infarction, unplanned reoperation, respiratory failure, or renal failure. Median length of stay was 4 days. All patients were discharged home. CONCLUSIONS: Totally endoscopic robotic mitral valve repair can be safely performed after a pretraining regimen with emphasis on experts' current practice and team training. After a pretraining regimen, cross-clamp times were not subject to learning curve phenomena but were dependent on procedural complexity. Nonclamp times were associated with a short learning curve.

BACKGROUND: Minimally invasive mitral valve surgery (MIMVS) has become a standard technique to perform mitral valve surgery in many cardiac centers. However, there remains a question regarding when MIMVS should not be performed due to an increased surgical risk. Consequently, expert surgeons were surveyed regarding their opinions on patient factors, mitral valve pathology and surgical skills in MIMVS. METHODS: Surgeons experienced in MIMVS were identified through an electronic search of the literature. A link to an online survey platform was sent to all surgeons, as well as two follow-up reminders. Survey responses were then submitted to a central database and analyzed. RESULTS: The survey was completed by 20 surgeons. Overall results were not uniform with regard to contraindications to performing MIMVS. Some respondents do not consider left atrial enlargement (95% of surgeons), complexity of surgery (75%), age (70%), aortic calcification (70%), EuroSCORE (60%), left ventricular ejection fraction (55%), or obesity (50%) to be contraindication to surgery. Ninety percent of respondents believe more than 20 cases are required to gain familiarity with the procedure, while 85% believe at least one MIMVS case needs to be performed per week to maintain proficiency. Eighty percent recommend establishment of multi-institutional databases and standardized surgical mentoring courses, while 75% believe MIMVS should be incorporated into current training programs for trainees. CONCLUSIONS: These results suggest that MIMVS has been accepted as a treatment option for patients with mitral valve pathologies according the expert panel. Initial training and continuing practice is recommended to maintain proficiency, as well as further research and formalization of training programs.

BACKGROUND: While it is known that band annuloplasty for functional mitral regurgitation (FMR) improves leaflet coaptation, the effect on regional coaptation geometry has not previously been well defined. We used three-dimensional transesophageal echocardiography (3D-TEE) to analyze the regional effects of semirigid band annuloplasty on annular geometry and leaflet coaptation zones of patients with FMR. METHODS: Sixteen patients with severe FMR underwent a semirigid band annuloplasty. Intraoperative full volume 3D-TEE datasets were acquired pre valve and post valve repair. Offline analysis assessed annular dimensions and regional coaptation zone geometry. The regions were defined as R1 (A1-P1), R2 (A2-P2), and R3 (A3-P3); coaptation distance, coaptation depth, and coaptation length were measured in each region. Differences were analyzed with repeated measures within a general linear model. RESULTS: Band annuloplasty decreased mitral regurgitation grade from 3.7 to 0.1 (scale 0 to 4). Annular septolateral dimension (p < 0.01) and coaptation distance (p < 0.01) decreased significantly in all regions. Likewise, anterior and posterior leaflet coaptation lengths increased in all regions (p < 0.01 and p = 0.05, respectively), with region 2 showing the greatest increase (p = 0.01). Changes in coaptation depth were not significant. CONCLUSIONS: Semirigid band annuloplasty for FMR produces significant regional remodeling of leaflet coaptation zones, with region 2 showing the greatest increase in leaflet coaptation length. This regional analysis of annular geometry and leaflet coaptation creates a framework to better understand the mechanisms of surgical success or failure of annuloplasty for FMR.

OBJECTIVE: Perfusion strategies and operative techniques for minimally invasive mitral valve repair have evolved over time. During the past decade, our institution's approach has progressed from a port access platform with femoral perfusion to predominantly a central aortic cannulation through a right anterior minithoracotomy incision. We analyzed this institutional experience to evaluate the impact of approach on patient outcomes. METHODS: Between 1995 and 2007, 1282 patients (mean age, 59.3 years; range, 18-99 years) underwent first-time, isolated mitral valve repair using a minimally invasive technique. Patient demographics included peripheral vascular disease (3.2%), chronic obstructive pulmonary disease (8.3%), atherosclerotic aorta (6.5%), cerebrovascular disease (4.3%), and ejection fraction less than 30% (4.3%). Retrograde perfusion was performed in 394 (30.7%) of all patients and endoaortic balloon occlusion in 373 (29.1%); the operative technique was a right anterior minithoracotomy in 1264 (98.6%) and left posterior minithoracotomy in 18 (1.4%). The etiology of mitral disease was degenerative in 73.2%, functional in 20.6%, and rheumatic in 2.4%. Data were collected prospectively using the New York State Cardiac Surgery Report System and a customized minimally invasive surgery data form. Logistic analysis was used to evaluate risk factors and outcomes; operative experience was divided into tertiles. RESULTS: Overall hospital mortality was 2.0% (25/1282). Mortality was 1.1% (10/939) for patients with degenerative etiology and 0.4% (3/693) for patients younger than 70 years of age with degenerative valve disease. Risk factors for death were advanced age (P = .007), functional etiology (P = .010; odds ratio [OR] = 3.3), chronic obstructive pulmonary disease (P = .013; OR = 3.4), peripheral vascular disease (P = .014; OR = 4.2), and atherosclerotic aorta (P = .03; OR = 2.8). Logistic risk factors for neurologic events were advanced age (P = .02), retrograde perfusion (P = .001; OR = 3.8), and emergency procedure (P = .01; OR = 66.6). Interaction modeling revealed that the only significant risk factor for neurologic event was the use of retrograde perfusion in high-risk patients with aortic disease (P = .04; OR = 8.5). Analysis of successive tertiles during this 12-year experience revealed a significant decrease in the use of retrograde arterial perfusion (89.6%, 10.4%, and 0.0%; P < .001) and endoaortic balloon occlusion (89.3%, 10.7%, and 0%; P < .001). The overall frequency of postoperative neurologic events was 2.3% (30/1282) and decreased from 4.7% in the first tertile to 1.2% in the second and third tertiles (P < .001). CONCLUSIONS: Central aortic cannulation through a right anterior minithoracotomy for mitral valve repair allows excellent outcomes in patients with a broad spectrum of comorbidities and has become our preferred approach for most patients undergoing mitral valve repair. Retrograde arterial perfusion is associated with an increased risk of stroke in patients with severe peripheral vascular disease and should be reserved for select patients without significant atherosclerosis.

BACKGROUND: A Society of Thoracic Surgeons' publication recently associated 'minimally invasive' approaches with increased neurologic complications; this proposed association was questionable due to imprecise definitions. To critically reevaluate this issue, we reviewed a large minimally invasive valve experience with robust definitions. METHODS: From November 1995 to January 2007, 3,180 isolated, non-reoperative valve operations were performed; 1,452 (45.7%) were aortic replacements and 1,728 (54.3%) were mitral valve procedures. Surgical approach was standard sternotomy (28%) or minimally invasive technique (72%). Antegrade arterial perfusion was used in 2,646 (83.2%) patients and retrograde perfusion in 534 (16.8%). Aortic clamping was direct in 83.4%, with endoclamp in 16.4% and no clamp in 0.2%. Patients were prospectively followed in a proprietary database and the New York State Cardiac Surgery Reporting System (mandatory, government audited). A neurologic event was defined as a permanent deficit, a transient deficit greater than 24 hours, or a new lesion on cerebral imaging. RESULTS: Hospital mortality for aortic valve replacement was 4.0% (sternotomy [5.1%] versus minimally invasive [3.4%] p = 0.13); for mitral procedures it was 2.4% (sternotomy [4.8%] versus minimally invasive [1.8%] p = 0.001). Multivariate analysis revealed that age, female gender, renal disease, ejection fraction less than 0.30, chronic obstructive pulmonary disease, and emergent operation were risk factors for mortality. Stroke occurred in 71 patients (2.2%) (sternotomy [2.1%] versus minimally invasive [2.3%] p = 0.82). Multivariate analysis of neurologic events revealed that cerebrovascular disease, emergency procedure, no-clamp, and retrograde perfusion were risk factors. In patients 50 years old or younger (n = 662), retrograde perfusion had no significant impact on neurologic events (1.6% vs 1.1%, p = 0.57). CONCLUSIONS: A minimally invasive approach with antegrade perfusion does not result in increased neurologic complications. Retrograde perfusion, however, is associated with increased neurologic risk in older patients