Faculty Bibliography

OBJECTIVES: The aim of this study was to identify reasons for and predictors of readmission. BACKGROUND: Short-term readmissions have been identified as an important cause of escalating health care costs, and coronary artery bypass graft (CABG) surgery is 1 of the most expensive procedures. METHODS: We retrospectively analyzed 30-day readmissions for 33,936 New York State patients who underwent CABG surgery between January 1, 2005, and November 30, 2007. The main reasons for readmission (principal diagnoses) and the significant independent predictors of readmission were identified. The hospital-level relationship between risk-adjusted mortality rate and risk-adjusted readmission rate was explored to determine the value of readmission rate as a complementary measure of quality. RESULTS: The most common reasons for readmission were post-operative infection (16.9%), heart failure (12.8%), and 'other complications of surgical and medical care' (9.8%). Increasing age, female sex, African-American race, higher body mass index, numerous comorbidities, 2 post-operative complications (renal failure and unplanned cardiac reoperation), Medicare or Medicaid status, discharges to a skilled nursing facility, saphenous vein grafts, and longer lengths of stay were all associated with higher rates of readmission. The correlation between the risk-adjusted 30-day readmission rate of hospitals and risk-adjusted in-hospital/30-day mortality rate was 0.32 (p = 0.047). The range across hospitals in the readmission rate was from 8.3% to 21.1%. CONCLUSIONS: The 30-day readmission rate for CABG surgery remains high, despite decreases in short-term mortality. Patients with any of the numerous risk factors for readmission should be closely monitored. Hospital readmission rates are not highly correlated with mortality rates and might serve as an independent quality measure

Abstract Objective: To determine predictors of low intensive care unit (ICU) admission hematocrit, and to determine if low hematocrit is associated with postoperative outcomes for coronary artery bypass graft (CABG) surgery with cardiopulmonary bypass. Methods: We performed a retrospective study of 8417 patients who underwent CABG surgery on cardiopulmonary bypass in New York in 2007. Patients with very low ICU admission hematocrit (</=21.9%) and low ICU admission hematocrit (22.0% to 25.9%) were identified. Significant independent predictors of low and very low ICU admission hematocrit, and the independent impact of each of these states on adverse outcomes were identified. Results: A total of 1.1% had very low hematocrit and 8.3% had low hematocrit. Significant independent predictors for either low or very low hematocrit included older age, females, lower body surface area, lower ventricular function, Hispanic ethnicity, non-Caucasian race, high creatinine, previous cardiac surgery, absence of left main disease, and emergency transfer to the operating room following catheterization or percutaneous coronary intervention. Patients with hematocrit </=21.9% had significantly higher risk-adjusted rates of postoperative bleeding (adjusted OR = 4.37, 95% CI [1.97, 9.68, respiratory failure (adjusted OR = 2.85, 95% CI [1.45, 5.63]), and one or more complications than patients with normal hematocrit. Patients with hematocrit between 22.0% and 25.9% also had higher complication rates. Conclusion: It is important for cardiovascular surgical teams to be aware of risk factors that predispose patients to unacceptable hematocrit values, to monitor values closely, and to treat accordingly in the operating room when low values occur. (J Card Surg 2010;25:638-646)

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

OBJECTIVE: The study objective was to determine predictors of hypothermia and hyperthermia, and the impact of hypothermia and hyperthermia on postoperative outcomes for off-pump coronary artery bypass grafting. METHODS: We performed a retrospective study of 2294 patients who underwent off-pump coronary artery bypass grafting in New York in 2007. Patients were classified as moderately to severely hypothermic (< or = 34.5 degrees C), mildly hypothermic (34.6 degrees C-35.9 degrees C), or mildly hyperthermic (37.5 degrees C-38.8 degrees C) after leaving the operating room. Significant independent predictors of these temperature states and the independent impact of each of these states on in-hospital mortality and complications were identified. RESULTS: A total of 37.7% of patients were mildly hypothermic, 9.0% of patients were moderately to severely hypothermic, and 5.6% of patients were mildly hyperthermic. Significant independent predictors for postoperative hypothermia included older age, female gender, lower body surface area, congestive heart failure, higher ventricular function, non-Hispanic ethnicity, single/double-vessel disease, low postoperative hematocrit, previous cardiac surgery, race other than white or black, and organ transplant. Patients with moderate to severe hypothermia had significantly higher risk-adjusted in-hospital mortality than patients with normothermia (adjusted odds ratio 3.00; 95% confidence interval, 1.11-8.08). Patients with mild hyperthermia also had significantly higher mortality (adjusted odds ratio 5.04; 95% confidence interval,1.18-21.55). Patients with either mild or moderate to severe hypothermia had significantly higher rates of respiratory failure and unplanned operations, and patients with mild hyperthermia had a significantly higher rate of respiratory failure than normothermic patients. CONCLUSION: It is important to maintain normal postsurgical core temperatures in patients who have undergone cardiac surgery to minimize or avoid death and complications

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

BACKGROUND: Short-term results with minimally invasive approaches for mitral valve repair in degenerative disease have been encouraging, with potential for diminishing blood loss and hospital length of stay. Little is known, however, about the long-term efficacy of this approach. This report analyzes a single institution's results over 12 years with minimally invasive mitral repair. METHODS: Since 1986, 3,057 patients have undergone mitral valve repair; 1,601 patients had degenerative disease and are the subject of this report. Minimally invasive mitral repair was done in 1071 patients with a right anterior minithoracotomy and direct vision. Clinical and echocardiographic variables were entered prospectively into a database. RESULTS: Hospital mortality was 2.2% for all patients (36 of 1601); 1.3% for isolated minimally invasive (9 of 712) and 1.3% (3 of 223) for isolated sternotomy mitral valve repair; and 3.6% (24 of 666) for valve repair plus a concomitant cardiac procedure. For isolated valve repair, 8-year freedom from reoperation was 91% +/- 2% for sternotomy and 95% +/- 1% for minimally invasive (p = 0.24), and 8-year freedom from reoperation or severe recurrent insufficiency was 90% +/- 2% for sternotomy and 93% +/- 1% for minimally invasive (p = 0.30). Eight-year freedom from all valve-related complications was 86% +/- 3% for sternotomy and 90% +/- 2% for minimally invasive (p = 0.14). CONCLUSIONS: These data indicate that long-term outcomes after minimally invasive mitral repair are excellent and equivalent to results achieved with sternotomy. In view of previously published advantages of short-term morbidity, minimally invasive approaches to mitral valve surgery deserve expanded use