Faculty Bibliography

Background: Covered stents have become part of the armamentarium for treating various esophageal pathologies. A recently available, low profile, fully covered metal stent with symmetrical flares (FCMSF) may offer improved deployment and resistance to migration. Methods: A retrospective review of 58 esophageal FCMSF placed in 47 consecutive patients by a single thoracic surgeon between March 2010 and February 2012 was performed. Pathologies included benign and malignant stricture and leak. Stents were placed endoscopically under general anesthesia using a 6 mm deployment system; bidirectional maneuverability was possible. Dysphagia score (0-4) was prospectively recorded. Leak treatment was assessed with postoperative esophagrams. Results: Mean age was 62.0 years. Sixteen of 58 stents (28%) were placed urgently/emergently. All patients had successful stent deployment with 0% stent-related hospital morbidity/mortality. Overall post-operative morbidity occurred following 12/58 stents, including arrhythmia, pneumonia, pneumothorax, urinary retention, hemodynamic instability, and COPD exacerbation. In patients with stricture (n = 29), mean dysphagia scores were reduced from 3.0 preoperatively to 1.2 post-operatively (p < 0.001). for leak, stent therapy (+/- drainage) avoided formal esophageal operation in 94% (17/18). Fifteen stents were removed during follow-up, 4 after migration. Mean overall survival was 2.3 +/- 2.6 months for stricture (21/35 remain alive) and 8.7 +/- 9.6 months for leak (16/18 remain alive). Mean duration of stent therapy was 4.9 +/- 4.8 months for stricture (29/35 remain in situ) and 3.5 +/- 3.2 months for leak (10/20 remain in situ). Mean hospital stay was 3.9 +/- 7.0 days. Discussion: FCMSF are an effective therapy for both esophageal strictures and leaks. The symmetrical covered flares likely contribute to the low observed migration rate

OBJECTIVES: The purpose of this study was to assess the impact of rosiglitazone on survival in patients with diabetes mellitus (DM) and coronary artery disease (CAD). METHODS: We carried out a drug-exposure analysis in 801 patients with DM and CAD in a cardiac catheterization laboratory registry (490 patients treated with a percutaneous coronary intervention, 224 patients treated with coronary artery bypass grafting, and 87 patients treated with medication alone). RESULTS: A total of 193 patients (24.1%) were exposed to rosiglitazone. The median survival from the date of cardiac catheterization in the rosiglitazone group was 146.7 months versus 109.1 months in the unexposed group (P<0.001). At 5 years, the unadjusted survival was 82% in the rosiglitazone-exposed group versus 69% in the unexposed group (P<0.001). There was no difference in survival between rosiglitazone-exposed and rosiglitazone-unexposed patients in the groups treated with coronary artery bypass grafting or medical therapy (P=0.37 and 0.11, respectively). In a multivariable model, rosiglitazone exposure had no effect on mortality (hazard ratio=0.737; 95% confidence interval: 0.521-1.044, P=0.86). CONCLUSION: We conclude that exposure to rosiglitazone is not associated with increased mortality in diabetics who are treated for CAD. These findings support the notion that insulin sensitization with a thiazolidinedione is safe in carefully selected and treated patients with DM and CAD.

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.

BACKGROUND: We sought to determine regional myofiber stress after Coapsys device (Myocor, Inc, Maple Grove, MN) implantation using a finite element model of the left ventricle (LV). Chronic ischemic mitral regurgitation is caused by LV remodeling after posterolateral myocardial infarction. The Coapsys device consists of a single trans-LV chord placed below the mitral valve such that when tensioned it alters LV shape and decreases chronic ischemic mitral regurgitation. METHODS: Finite element models of the LV were based on magnetic resonance images obtained before (preoperatively) and after (postoperatively) coronary artery bypass grafting with Coapsys implantation in a single patient. To determine the effect of Coapsys and LV before stress, virtual Coapsys was performed on the preoperative model. Diastolic and systolic material variables in the preoperative, postoperative, and virtual Coapsys models were adjusted so that model LV volume agreed with magnetic resonance imaging data. Chronic ischemic mitral regurgitation was abolished in the postoperative models. In each case, myofiber stress and pump function were calculated. RESULTS: Both postoperative and virtual Coapsys models shifted end-systolic and end-diastolic pressure-volume relationships to the left. As a consequence and because chronic ischemic mitral regurgitation was reduced after Coapsys, pump function was unchanged. Coapsys decreased myofiber stress at end-diastole and end-systole in both the remote and infarct regions of the myocardium. However, knowledge of Coapsys and LV prestress was necessary for accurate calculation of LV myofiber stress, especially in the remote zone. CONCLUSIONS: Coapsys decreases myofiber stress at end-diastole and end-systole. The improvement in myofiber stress may contribute to the long-term effect of Coapsys on LV remodeling.

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