Faculty Bibliography

OBJECTIVE: Recent Society of Thoracic Surgeons and Society of Cardiovascular Anesthesiologists (STS/SCA) guidelines highlight the safety of blood conservation strategies in routine cardiac surgery. We evaluated the feasibility and impact of such a program in complex aortic surgery. METHODS: Between March 2010 and October 2011, 63 consecutive aortic replacement procedures were performed: aortic root (n = 17; 27%), ascending aorta (n = 15; 23.8%), aortic arch (n = 19; 30.2%), descending aorta (n = 8; 12.7%), and thoracoabdominal aorta (n = 4; 6.3%). Aortic dissections were present in 32 patients. A multidisciplinary approach to blood conservation included minimal perioperative crystalloid, small priming circuits, hemoconcentration, meticulous hemostasis, and tolerance of postoperative anemia (hemoglobin of >/= 7mg/dL). RESULTS: Operative mortality was 11.1%. Multivariate predictors of mortality were low preoperative hematocrit (HCT, P = 0.05) and endocarditis (P = 0.021). Seventy-four percent of patients required no intraoperative packed red blood cell (pRBC) transfusion. For nondissection patients, 80.6% required /= 2 U (P = 0.001). CONCLUSIONS: These findings demonstrate that a perioperative blood conservation management strategy can be extended to complex aortic surgery and is associated with better clinical outcomes.

The Hypothesis 2 arm of the STICH trial compared outcomes in ischemic cardiomyopathy patients undergoing CABG plus SVR vs. CABG alone. Although the trial results suggest equivalency of these therapies, important trial flaws have been identified which cast critical doubt regarding the generalizability of the trial findings.

Increased platelet activity is associated with adverse cardiovascular events. The mean platelet volume (MPV) correlates with platelet activity; however, the relation between the MPV and long-term mortality in patients undergoing percutaneous coronary intervention (PCI) is not well established. Furthermore, the role of change in the MPV over time has not been previously evaluated. We evaluated the MPV at baseline, 30 days, 60 days, 90 days, 1 year, 2 years, and 3 years after the procedure in 1,512 patients who underwent PCI. The speed of change in the MPV was estimated using the slope of linear regression. Mortality was determined by query of the Social Security Death Index. During a median of 8.7 years, mortality was 49.3% after PCI. No significant difference was seen in mortality when stratified by MPV quartile (first quartile, 50.1%; second quartile, 47.7%; third quartile, 51.3%; fourth quartile, 48.3%; p = 0.74). For the 839 patients with available data to determine a change in the MPV over time after PCI, mortality was 49.1% and was significantly greater in patients with an increase (52.9%) than in those with a decrease (44.2%) or no change (49.1%) in the MPV over time (p <0.0001). In conclusion, no association was found between the baseline MPV and long-term mortality in patients undergoing PCI. However, increased mortality was found when the MPV increased over time after PCI. Monitoring the MPV after coronary revascularization might play a role in risk stratification.

OBJECTIVES: Simulated mitral valve replacement may aid in the assessment of technical skills required for adequate performance in the operating room. We sought to design and assess a mitral valve replacement training station that is low-cost, nonperishable, portable, and reproducible as a first step in developing a mitral valve surgical skills curriculum. METHODS: Nineteen physicians (7 general surgery residents, 8 cardiothoracic surgery residents, and 4 attending cardiothoracic surgeons) underwent simulated mitral valve replacement testing. Simulated mitral valve replacement was performed on a training station consisting of a replaceable "mitral annulus" inside a restrictive "left atrium." Eight components of performance were graded on a 5-point scale. A composite score (100 point maximum) was calculated by weighting the grades by procedural time. The effect of training level was evaluated using analysis of variance and post hoc Tukey honestly significant difference. RESULTS: The speed of simulated mitral valve replacement varied among general surgery residents, cardiothoracic surgery residents, and attending cardiothoracic surgeons (52.9 +/- 9.0 vs 32.8 +/- 4.7 vs 28.0 +/- 3.5 minutes, respectively; F = 25.3; P < .001). Level of training significantly affected all 8 evaluation components (P < .001). Composite scores increased with level of training (general surgery residents 32.9 +/- 11.4, cardiothoracic surgery residents 65.1 +/- 11.5, and attending cardiothoracic surgeons 88.3 +/- 7.8 of a possible 100 points; F = 35.7; P < .001). Cardiothoracic surgery residents who reported having performed 10 to 50 mitral valve replacements as the primary surgeon had a composite score of 65.0 +/- 2.8 (P < .01 compared with attending cardiothoracic surgeons). CONCLUSIONS: Simulated mitral valve replacement can be performed using this simple, affordable, portable setup. Performance scores correlate with level of training and experience, but residents who performed 10 to 50 mitral valve replacements still failed to reach attending-level proficiency. This training simulator may facilitate skills practice and evaluation of competency in cardiac surgery trainees.

OBJECTIVE: To understand how teaching behaviors contribute to simulation-based learning, we used a 7-category educational framework to assess the teaching behaviors used in basic skills training. METHODS: Twenty-four first-year cardiothoracic surgery residents and 20 faculty participated in the Boot Camp vessel anastomosis sessions. A portable chest model with synthetic graft and target vessels and a tissue-based porcine model simulated coronary artery anastomosis. After each 2-hour session on days 1 and 2, residents assessed teaching behaviors of faculty using a 20-item questionnaire based on the 5-point Likert scale. After session on day 1, faculty completed a self-assessment questionnaire. At 3 months, faculty completed self-assessment questionnaires regarding teaching behaviors in simulation and clinical settings. Each questionnaire item represents 1 or more teaching categories: "learning climate," "control of session," "communication of goals," "promoting understanding and retention," "evaluation," "feedback," and "self-directed learning." RESULTS: Generally, resident ratings indicated that faculty showed positive teaching behaviors. Faculty self-assessment ratings were all lower (P < .025) than those assigned to them by the residents except for 1 component representative of "feedback," which approached significance (P = .04); 2 items, representative of "promoting understanding and retention" and "evaluation", had mean scores of less than 3. At 3 months, compared with self-assessment at Boot Camp, faculty ratings suggested improved teaching behaviors in their simulation settings in the following: "learning climate," "control of session," "communication of goals," "promoting understanding and retention," and "evaluation." The simulation environment was perceived as more positive for technical skills training in certain aspects compared with clinical setting: instructor reviewed function and operation of equipment with learner before session (representative of "promoting understanding and retention") and instructor allowed the learner ample time to practice (representative of "control of session" and "promoting understanding and retention") (P < .025). CONCLUSIONS: Simulation-based skills training is perceived by residents to be associated with positive teaching behaviors. Faculty self-ratings indicate that they do not always use many of these teaching behaviors and that their performance can be improved. The simulation setting may provide greater opportunity for positive teaching behaviors compared with the clinical environment.

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: 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.

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.