Is body mass index a risk factor for isolated off-pump coronary revascularization?

OBJECTIVE: The influence of body mass index (BMI) as a risk factor for isolated off-pump coronary artery bypass (OPCAB) surgery is unknown. We postulated that BMI ≥ 30 kg/m(2) would adversely affect outcomes following OPCAB at our institution. METHODS: From 2002 to 2009, we selected 742 patients (primary, N = 709 [95.6%], re-operative, N = 33 [4.45%]) who underwent isolated OPCAB for analysis. Patients were stratified into groups by BMI: non-obese (BMI < 30 kg/m(2) ) and obese (BMI ≥ 30 kg/m(2)). Preoperative risk, operative characteristics, and postoperative outcomes were analyzed. Risk-adjusted models evaluated the occurrence of any complication and mortality. RESULTS: Overall crude mortality was 1.5% (11/742). When compared to non-obese (26.12 ± 2.72 kg/m(2)) recipients, the obese (35.81 ± 5.69 kg/m(2)) comprised younger patients (62.46 ± 9.96 years, p < 0.001). Number of diseased vessels, Left ventricular ejection fraction, and baseline renal function was equivalent across groups. Diabetes (53.24%) and hypertension (90.59%) were more prevalent among obese patients (p < 0.001, respectively). Internal mammary artery utilization (p = 0.47), endoscopic vein harvest (p = 0.74), and intra-aortic balloon pump use (p = 0.58) were similar between groups. Interestingly, postoperative blood product requirement was lower in obese versus non-obese recipients (47.35% vs. 56.72%, p < 0.01). Furthermore, intensive care unit stay (p = 0.93), mortality (p = 0.56), and discharge to home (p = 0.09) remained equivalent between groups. Importantly, multivariable logistic regression did not identify BMI ≥ 30 kg/m(2) as an independent predictor of any complication (p = 0.21) or mortality (p = 0.74). CONCLUSIONS: Obesity does not influence operative characteristics or effect outcomes after OPCAB. BMI ≥ 30 kg/m(2) should not be considered a prohibitive risk factor in isolated off-pump coronary revascularization.

Whole blood cardioplegia (minicardioplegia) reduces myocardial edema after ischemic injury and cardiopulmonary bypass.

While blood:crystalloid cardioplegia is the clinical standard for patients undergoing cardiopulmonary bypass (CPB), it has been postulated that whole blood minicardioplegia may benefit the severely injured heart by reducing cardioplegic volume, thereby reducing myocardial edema. To test this hypothesis, we compared the cardioprotection of a popular 4:1 blood:crystalloid cardioplegia to whole blood minicardioplegia (WB) in a porcine model of acute myocardial ischemia. Yorkshire pigs (n = 20) were placed on atriofemoral bypass and subjected to 30 minutes of global normothermic ischemia. Animals were randomized to receive either 4:1 cold cardioplegia (n = 10) or WB cold cardioplegia (n = 10) delivered antegrade continuously for 90 minutes. Baseline (BL) echocardiographic determination of left ventricular mass (LVM) was compared within groups for cardiac edema (%) measured by histologic morphometrics. All (100%) animals receiving WB were successfully weaned off CPB, whereas only 40% of animals receiving 4:1 were successfully weaned off CPB. Cardiac edema percentage (p < .004) and LVM (p < .05) were significantly decreased in the WB group compared with 4:1. WB cardioplegia increases the number of hearts successfully weaned from CPB and decreases cardiac edema in our porcine model of acute myocardial ischemia. This finding implies whole blood cardioplegia may be more protective in a select group of patients undergoing extended CPB time by decreasing myocardial edema.

Robot-assisted mitral valve repair: a single institution review.

OBJECTIVE: Mitral valve repair (MVR) is the definitive therapy for mitral myxomatous degeneration. Median sternotomy has been the traditional approach to repair until the advent of the da Vinci Surgical System (Intuitive Surgical, Inc., Sunnyvale, CA). Minimally invasive surgical approaches for mitral repair have been slow to gain acceptance in cardiac surgery. We review the MVR results from our single-institution academic robotic program. METHODS: From August 2004 through April 2008, patients who underwent a robotic-assisted (RA) MVR were identified. RA technique included a 4-cm right minithoracotomy, femoral cardiopulmonary bypass with transthoracic aortic occlusion, and RA-MVR. Repair types were combinations of quadrangular/triangular leaflet resection, sliding plasty, chordal transfer/replacement, and edge-to-edge approximation, with band annuloplasty in all cases. Postrepair echocardiography and morbidity follow-ups were completed in all patients. Our primary outcome was adequacy of repair, and secondary outcome was major complications. RESULTS: There were 43 patients (29 male and 14 female) who underwent RA-MVR for severe (4+) mitral regurgitation during the 4-year review. Average operative time was 272.26 minutes. Only one patient had mild postoperative mitral regurgitation, whereas 20 had trace and 22 had no regurgitation after repair. Mean ventilator time was 32.1 hours, and length of stay was 5.7 days. One third of the patients (33%) received postoperative-packed red blood cell transfusions (average: 2.4 units per patient). Twenty-eight percent of patients developed atrial fibrillation after repair. Most of the patients (95.3%) were discharged home. There were no 30-day mortalities. CONCLUSIONS: Based on our small single-institution experience, RA-MVR provides an effective treatment for severe mitral valve regurgitation. Although procedure durability is slowly being established, preliminary results are promising. Careful programmatic advances with an integrated team approach can facilitate acceptable postoperative outcomes and excellent MVR.