Impact of Body Mass Index on Outcomes in Cardiac Surgery.

OBJECTIVES: Body mass index (BMI) commonly is used in obesity classification as a surrogate measure, and obesity is associated with a cluster of risk factors for cardiovascular disease. The aim of this study was to investigate the impact of BMI on short-term outcomes after cardiac surgery. DESIGN: A retrospective cohort study. SETTING: University teaching hospital, 2 centers. PARTICIPANTS: The study comprised 4,740 patients who underwent cardiac surgery at 2 hospitals-from July 1, 2001, to June 30, 2013, in 1 hospital and from September 1, 2003, to August 31, 2014, in a second hospital. INTERVENTIONS: No changes to standard practice were required. MEASUREMENTS AND MAIN RESULTS: Patients were assigned into 6 BMI groups as follows: underweight (BMI<18.5 kg/m(2)), normal weight (≥18.5 to<25 kg/m(2)), overweight (≥25 to<30 kg/m(2)), class I obese (≥30 to<35 kg/m(2)), class II obese (≥35 to<40 kg/m(2)), and class III obese (BMI≥40 kg/m(2)). Short-term major postoperative complications (postoperative stroke, cardiac arrest, new atrial fibrillation/flutter, permanent rhythm device insertion, deep sternal infection, sepsis, prolonged ventilation, pneumonia, renal dialysis, renal failure, intensive care unit readmission, total intensive care unit hours, and readmission in 30 days, and mortalities (in-hospital mortality, 30-day mortality, surgical mortality) were compared among various BMI groups after cardiac surgery. Age, sex, surgery type, family history of coronary artery disease, diabetes, hypertension, heart failure, and lipid-lowering medication were the risk factors for early outcomes. Multiple logistic regression analysis indicated that the underweight and class III obese BMI groups demonstrated significant, adverse differences in some short-term outcomes, including deep sternal infection, prolonged ventilation, new atrial fibrillation/flutter, and renal failure. However, being in the overweight or class I obese group demonstrated a positive effect on discharge and surgical mortality. CONCLUSIONS: The results of this study demonstrated that extreme obesity and underweight were significantly associated with early major adverse clinical outcomes. However, there was an "obese paradox" in short-term mortality after cardiac surgery.

The Effect of Aspirin on Bleeding and Transfusion in Contemporary Cardiac Surgery.

OBJECTIVE: Despite evidence that preoperative aspirin improves outcomes in cardiac surgery, recommendations for aspirin use are inconsistent due to aspirin's anti-platelet effect and concern for bleeding. The purpose of this study was to investigate preoperative aspirin use and its effect on bleeding and transfusion in cardiac surgery. METHODS: This retrospective study involved consecutive patients (n=1571) who underwent CABG, valve, or combined CABG and valve surgery at a single center between March 2007 and July 2012. Of all patients, 728 met the inclusion criteria and were divided into two groups: those using (n=603) or not using (n=125) aspirin within 5 days of surgery. Data were collected on chest tube drainage, re-operation for bleeding, and transfusion of red blood cells (RBCs), fresh frozen plasma (FFP), and platelets. RESULTS: No significant difference was observed between the two groups in chest tube drainage or re-operation for bleeding. An increase in patients transfused with RBCs was observed in the aspirin group (61.9 vs 51.2%, adjusted OR 1.77, p=0.027); however, among those transfused RBCs, no significant difference in mean units transfused or massive transfusion was observed. No significant difference was seen in transfusion requirement of FFP or platelets. CONCLUSIONS: In patients undergoing CABG, valve, or combined CABG/valve surgery, preoperative aspirin, within 5 days of surgery, was associated with an increased probability of receiving an RBC transfusion. Preoperative aspirin was not associated with an increase in chest tube drainage, re-operation for bleeding complications, or transfusion of FFP or platelets.

Evidence for preoperative aspirin improving major outcomes in patients with chronic kidney disease undergoing cardiac surgery: a cohort study.

BACKGROUND: Effects of aspirin on patients with chronic kidney disease (CKD) remains unclear. This study aimed to examine the effect of preoperative aspirin use on postoperative renal function and 30-day mortality in patients with CKD undergoing cardiac surgery. METHODS: A retrospective cohort study was performed on consecutive patients (n = 5175) receiving cardiac surgery in 2 tertiary hospitals. Of all patients, 3585 met the inclusion criteria and underwent the analysis to determine the association of preoperative aspirin with incidence of acute kidney injury (AKI) and death based on estimated glomerular filtration rate (eGFR). RESULTS: Of 3585 patients, 31.5% had CKD (eGFR < 60 mL/min/1.73 m2) at baseline and 27.6% had AKI postoperatively. The baseline eGFR had a nonlinear relationship with the incidence and stages of AKI. As eGFR decreased to 15 to 30 from more than or equal to 90 mL/min/1.73 m2, AKI and 30-day mortality increased to 50.5% from 23.5% and to 11.9% from 2.6%, respectively (P < 0.001). However, preoperative aspirin use was associated with a significant decrease in postoperative AKI and 30-day mortality in patients with CKD undergoing cardiac surgery, in particular, the survival benefit associated with aspirin was greater in patients with CKD (vs normal kidney function): 30-day mortality was reduced by 23.3%, 58.2%, or 70.0% for patients with baseline eGFR more than or equal to 90, 30 to 59, or 15 to 30 mL/min/1.73 m2, respectively (P trend < 0.001). CONCLUSIONS: For patients with CKD undergoing cardiac surgery, preoperative aspirin therapy was associated with renal protection and mortality decline. The magnitude of the survival benefit was greater in patients with CKD than normal kidney function.

Surgical removal of a large mobile left ventricular thrombus via left atriotomy.

Left ventricular (LV) thrombus is a life-threatening complication of severe LV dysfunction. Ventriculotomy has been a commonly performed procedure for LV thrombus; however, it often further decrease LV function after surgery. We present an alternative approach to thrombectomy in order to minimize the postoperative LV dysfunction. A 37-year-old female with a postpartum cardiomyopathy found to have poor LV function and a large left ventricular apical thrombus (3 cm × 3 cm) attached to the apex by a narrow stalk. Given her severe LV dysfunction, the LV thrombus was approached via left atriotomy under cardiopulmonary bypass. The LV thrombus was easily extracted with gentle traction via the mitral valve. Postoperatively, the patient was discharged home without any embolization event or inotropic support. LV thrombectomy via left atriotomy through the mitral valve could be an alternative option for the patients with poor LV function with a mobile LV thrombus.

Effects of preoperative aspirin on cardiocerebral and renal complications in non-emergent cardiac surgery patients: a sub-group and cohort study.

BACKGROUND AND OBJECTIVE: Postoperative cardiocerebral and renal complications are a major threat for patients undergoing cardiac surgery. This study was aimed to examine the effect of preoperative aspirin use on patients undergoing cardiac surgery. METHODS: An observational cohort study was performed on consecutive patients (n = 1879) receiving cardiac surgery at this institution. The patients excluded from the study were those with preoperative anticoagulants, unknown aspirin use, or underwent emergent cardiac surgery. Outcome events included were 30-day mortality, renal failure, readmission and a composite outcome--major adverse cardiocerebral events (MACE) that include permanent or transient stroke, coma, perioperative myocardial infarction (MI), heart block and cardiac arrest. RESULTS: Of all patients, 1145 patients met the inclusion criteria and were divided into two groups: those taking (n = 858) or not taking (n = 287) aspirin within 5 days preceding surgery. Patients with aspirin presented significantly more with history of hypertension, diabetes, peripheral arterial disease, previous MI, angina and older age. With propensity scores adjusted and multivariate logistic regression, however, this study showed that preoperative aspirin therapy (vs. no aspirin) significantly reduced the risk of MACE (8.4% vs. 12.5%, odds ratio [OR] 0.585, 95% CI 0.355-0.964, P = 0.035), postoperative renal failure (2.6% vs. 5.2%, OR 0.438, CI 0.203-0.945, P = 0.035) and dialysis required (0.8% vs. 3.1%, OR 0.230, CI 0.071-0.742, P = 0.014), but did not significantly reduce 30-day mortality (4.1% vs. 5.8%, OR 0.744, CI 0.376-1.472, P = 0.396) nor it increased readmissions in the patients undergoing cardiac surgery. CONCLUSIONS: Preoperative aspirin therapy is associated with a significant decrease in the risk of MACE and renal failure and did not increase readmissions in patients undergoing non-emergent cardiac surgery.

Preoperative aspirin use and outcomes in cardiac surgery patients.

BACKGROUND: The effects of preoperative aspirin use on outcomes of cardiac surgery patients remain uncertain. This study was aimed to evaluate the effect of preoperative aspirin use on major outcomes in cardiac surgery patients. METHODS: An observational cohort study was performed on consecutive patients (n = 4256) undergoing cardiac surgery in 2 tertiary hospitals. Of all patients, 2868 patients met the inclusion criteria and were divided into 2 groups: those taking (n = 1923) or not taking (n = 945) aspirin within 5 days preceding surgery. RESULTS: Patients in the aspirin group presented significantly more with comorbidities including hypertension, diabetes, peripheral arterial disease, previous myocardial infarction, angina, cerebrovascular disease, older age, and male gender. With propensity scores adjusted and multivariate logistic regression, however, the results of this study showed that preoperative aspirin therapy (vs nonaspirin) significantly reduced the risk of 30-day mortality (3.5% vs 6.5%, OR: 0.611, 95% CI: 0.391-0.956, P = 0.031), postoperative renal failure (3.7% vs 7.1%, OR: 0.384, 95% CI: 0.254-0.579, P < 0.001), dialysis required (1.9% vs 3.6%, OR: 0.441, 95% CI: 0.254-0.579, P < 0.001), intensive care unit stay (mean 107.2 vs 136.1 h, P < 0.001) and a composite outcome-major adverse cardiocerebral events (8.7% vs 10.8%, OR: 0.662, 95% CI:: 0.482-0.909, P = 0.011) in the patients undergoing cardiac surgery. However, readmissions did not show a significant difference between the 2 groups (14.5% vs 12.8%, P = 0.944). CONCLUSIONS: Preoperative aspirin therapy is associated with a significant decrease in the risk of major cardiocerebral complications, renal failure, intensive care unit stay and 30-day mortality but does not increase the risk of readmissions in patients undergoing cardiac surgery.

Robot-assisted thymectomy is superior to transsternal thymectomy.

BACKGROUND: Complete thymectomy is the procedure of choice in the treatment of thymomas and in treating selected patients with myasthenia gravis. Transsternal thymectomy is the gold standard for most patients. Robot-assisted thymectomy has emerged as an alternative to open transsternal surgery. The goal of this study was to compare perioperative outcomes in patients who underwent transsternal or robot-assisted thymectomy. METHODS: We performed a retrospective review of all patients who underwent robot-assisted or transsternal thymectomy at our institution from February 2001 to February 2010. Data are presented as mean ± SD. Significance was set as P < 0.05. RESULTS: Fifty patients underwent either transsternal (n = 35) or robot-assisted (n = 15) thymectomy. Patient demographics and the incidence of myasthenia gravis were similar between groups. There were no intraoperative complications or conversions to open surgery in the robot-assisted group. Intraoperative blood loss was significantly higher in the transsternal group (151.43 vs. 41.67 ml, P = 0.01). There were 20 postoperative complications and 1 postoperative death in the transsternal group and 1 postoperative complication in the robot-assisted group (P = 0.001). Hospital length of stay was 4 days (range 2-27 days) in the transsternal group and 1 day (range 1-7 days) in the robot-assisted group (P = 0.002). CONCLUSIONS: Robot-assisted thymectomy is superior to transsternal thymectomy, reducing intraoperative blood loss, postoperative complications, and hospital length of stay. Further investigation of the long-term oncologic results in thymoma patients and long-term remission rates in patients with myasthenia gravis who underwent robot-assisted thymectomy is warranted.

Surgical treatment of infective endocarditis in patients undergoing chronic hemodialysis.

BACKGROUND AND AIM OF THE STUDY: Infective endocarditis (IE) is a devastating complication in patients undergoing chronic hemodialysis (HD). The study aim was to reveal the characteristics and outcomes of surgically managed IE in chronic HD patients. METHODS: Between April 1998 and August 2011, a total of 119 patients underwent surgery to treat IE. Of these patients, 16 were receiving chronic HD preoperatively. A comparison between non-HD patients (n = 103) and HD patients (n = 16) was conducted with regards to perioperative variables and postoperative morbidity and mortality. A survival analysis was performed using the Kaplan-Meier method. RESULTS: Preoperatively, a greater proportion of HD patients had diabetes mellitus than did non-HD patients (44% versus 16%, p = 0.015). Staphylococcus spp. (56%) and Enterococcus spp. (25%) were the predominant microorganisms in HD patients, while Staphylococcus spp. (37%) and Streptococcus spp. (21%) were predominant in non-HD patients. The most affected valve position was the aortic valve, followed by the mitral and the tricuspid in both groups. An annular reconstruction was performed in 56% of HD patients and in 30% of non-HD patients (p = 0.039). The HD patients had a higher incidence of perioperative use of intra-aortic balloon pump placement (25% versus 6.9%, p = 0.042), postoperative open-chest management (38% versus 9.8%, p = 0.009), and prolonged ventilation (63% versus 33%, p = 0.025). The operative mortality was 9.7% in non-HD patients and 38% in HD patients (p = 0.008). Survival at one year was 82% in the non-HD group and 34% in the HD group (p < 0.001). Multivariable analysis revealed that chronic HD is an independent predictor of operative and long-term mortality. CONCLUSION: The operative outcome after endocarditis in HD patients remains poor, and the importance of preventing endocarditis in chronic HD patients is further emphasized.

Single-stage operation for giant substernal goiter with severe coronary artery disease.

A 76-year-old female, with a history of asthma and tracheal bronchitis, presented with a non-ST elevation, myocardial infarction. Chest x-ray on admission showed a widened mediastinum, which was further evaluated with a computed tomography (CT) scan. It disclosed a giant substernal goiter compressing the trachea and the ascending aorta. Cardiac catheterization showed significant coronary disease unsuitable for percutaneous intervention; thus, the patient was scheduled for coronary artery bypass grafting. Single stage thyroidectomy immediately followed by coronary artery bypass was performed. After surgery, her upper airway symptoms were improved, and no cardiac events were noted. Collaboration between otolaryngology and thoracic surgery teams contributed to good outcomes for this patient with substernal goiter and severe cardiac disease.

Conventional aortic valve replacement for elderly patients in the current era.

BACKGROUND: Because of the rising expectation of prolonged life in the general population and the recent recognition of undertreated aortic valve disease in the elderly, updating the available results of aortic valve surgery is imperative, especially considering the rapid evolution of the transcatheter valve implantation procedure. METHODS AND RESULTS: Between 1997 and 2010, 308 patients aged 70 years or older underwent aortic valve replacement (AVR) for aortic stenosis (AS). Short- and long-term results were analyzed and risk factors for long-term mortality were determined. Mean age was 78.5 years and 124 patients were aged 80 or older. Concomitant coronary artery bypass grafting (CABG) was performed in 46% of the cases. Mean left ventricular ejection fraction (LVEF) was 52%. Overall observed and expected operative mortality using the Society of Thoracic Surgeons-Predicted Risk of Mortality score was 3.9% and 4.8%, respectively. Overall survival rates at 1, 5, and 10 years were 88.6%, 71.6%, and 31.8%, respectively. Predictors of long-term mortality included diabetes; preoperative shock; LVEF ≤ 40%; New York Heart Association functional class III or IV; and age. CONCLUSIONS: Short- and long-term results of conventional AVR in the elderly prove it to be durable and, especially in relatively low-risk patients and patients who require concomitant CABG, operative mortality is reasonably low. Conventional AVR ± CABG remains the gold standard for elderly patients with AS.

Rigid sternal fixation improves postoperative recovery.

INTRODUCTION: During the past five years, ridged sternal fixation has been utilized for sternal closure after cardiac surgery. It is known that this procedure provides better sternal stability; however, its contribution to patient recovery has not been investigated. METHODS: Retrospective chart review was conducted for patients who underwent CABG and/or valve surgery in our institution between 2009 and 2010. Preoperative, perioperative, and follow-up data of patients with ridgid fixation (group R, n=89) were collected and compared with those patients with conventional sternal closure (group C, n=133). The decision regarding the sternal closure method was based on the surgeon's preferences. Univariate followed by multivariate analyses were performed to evaluate the dominant factor of sternal lock usage and to evaluate postoperative recoveries. The factors included in the analyses were; age, sex, coronary risk factors, urgency of surgery, ejection fraction, coronary anatomy, preoperative stroke, renal function, and preoperative presence of heart failure. All statistical analyses were performed by JMP software. RESULTS: Group R was younger (62 ± 9 in group R vs 69 ± 11 in group C, p<0.0001) than group C, more male dominant (61% vs 49%, p=0.0452), had a lower percentage of patients undergoing redo-surgery (2.2% vs 9.0%, p<0.0418), was more likely to be used in isolated coronary artery bypass grafting (71% vs 46%, p=0.0002), more often to be used for large patient (body mass index, BMI greater than 30) (58% vs 37%. P=0.0045), and patients were more likely to have a low EuroSCORE (2.6 ± 2.3 vs 4.4 ± 2.7). Intubation time (13 ± 20 hours vs 39 ± 97 hours, p=0.0030), ICU stay (58 ± 40 hours vs 99 ± 119 hours, p=0.0003), and postoperative length of stay (7.0 ± 3.7 days vs 8.4 ± 4.7 days, p<0.0141) were significantly shorter in group R than group C. Multivariate analyses showed ridged sternal fixation was the most dominant factor affecting intubation time and ICU stay. CONCLUSION: Rigid sternal fixation systems were more frequently applied to low risk young male patients. Among these selected patients, ridgid sternal fixation can contribute to early patient recovery.

Preoperative renin-angiotensin system inhibitors protect renal function in aging patients undergoing cardiac surgery.

BACKGROUND: Renal failure (RF) represents a major postoperative complication for elderly patients undergoing cardiac surgery. This observational cohort study examines effects of preoperative use of renin-angiotensin system (RAS) inhibitors on postoperative renal failure in aging patients undergoing cardiac surgery. METHODS AND RESULTS: We retrospectively analyzed a cohort of 1287 patients who underwent cardiac surgery at this institution (2003-2007). The patients included were ≥65 years old, scheduled for elective cardiac surgery, and without preexisting RF (defined by the criteria of the Society of Thoracic Surgeons as described in Method). Of all patients evaluated, 346 patients met the inclusion criteria and were divided into two groups: using (n = 122) or not using (n = 224) preoperative RAS inhibitors. A comparison of the two groups showed no significant differences in baseline parameters, including creatinine clearance, body mass index, history of diabetes and smoking, preoperative medicines (except that more patients with RAS inhibitors had a history of hypertension or congestive heart failure, fewer RAS inhibitor patients had chronic lung disease), in intraoperative perfusion and aortic cross-clamp time, and in postoperative complications and 30-d mortality. Multivariate logistic regression analysis demonstrated, however, that preoperative RAS inhibitors significantly and independently reduced the incidence of postoperative RF in the patients undergoing cardiac surgery compared with those not taking RAS inhibitors: 1.6% versus 7.6%, yielding an odds ratio of 0.19 (95 % CI 0.04-0.84, P = 0.029). CONCLUSIONS: Preoperative RAS inhibitors may have significant renoprotective effects for aging patients undergoing elective cardiac surgery.

Modified inferior vena caval anastomosis to reduce tricuspid valve regurgitation after heart transplantation.

Postoperative tricuspid valve regurgitation is moderate to severe in 15% to 20% of heart transplant recipients despite use of the bicaval surgical technique. We hypothesized that the regurgitation might be partly due to increased tension on the donor right atrium. To study the right atrial distortion, we modified the standard bicaval anastomosis. Our technique involves augmenting the donor right atrial anterior wall with a flap of the recipient's right atrium, which is left attached in continuity with the anterior aspect of the inferior vena cava along 65% of its circumference. We measured tricuspid regurgitation, right atrial area, and right atrioventricular diameter in 7 consecutive patients who underwent orthotopic heart transplantation with the modified anastomosis. Tricuspid regurgitation was graded as follows: 1 = trace, <10%; 2 = mild, 10%-24%; 3 = moderate, 25%-50%; and 4 = severe, >50%. All patients were weaned from inotropic support within 1 week after transplantation with excellent ventricular function, no heart block, and 100% survival at 30 days. The median follow-up time was 173 days (44-358 days). Other median measurements included tricuspid valve regurgitation jet area, 0.30 cm(2) (0-1.90 cm(2)); right atrial area, 15.90 cm(2) (14.47-18.00 cm(2)); atrioventricular diameter, 2.70 cm (2.63-3.09 cm); and tricuspid regurgitation, 1.67% (0-12.42%). Mild regurgitation occurred in 1 recipient; in all others, it was trace. The modified inferior vena caval anastomosis is simple and safe. It eliminates moderate and severe tricuspid valve regurgitation without routine annuloplasty after orthotopic heart transplantation via the bicaval technique.

Ductus arteriosus aneurysm in an adult patient presenting with hoarseness.

Aneurysm of the ductus arteriosus is a rare diagnosis, with most cases found in the pediatric population. The unusual adult cases reported in the literature have been associated with high morbidity and a surgical repair has been recommended. We report a case of a 60-year-old man who presented with hoarseness secondary to a ductus arteriosus aneurysm and underwent a repair of this abnormality via a left posterolateral thoracotomy utilizing partial cardiopulmonary bypass.

Human epicardial adipose tissue is a source of inflammatory mediators.

BACKGROUND: Inflammatory mediators that originate in vascular and extravascular tissues promote coronary lesion formation. Adipose tissue may function as an endocrine organ that contributes to an inflammatory burden in patients at risk of cardiovascular complications. In this study, we sought to compare expression of inflammatory mediators in epicardial and subcutaneous adipose stores in patients with critical CAD. METHODS AND RESULTS: Paired samples of epicardial and subcutaneous adipose tissues were harvested at the outset of elective CABG surgery (n=42; age 65+/-10 years). Local expression of chemokine (monocyte chemotactic protein [MCP]-1) and inflammatory cytokines (interleukin [IL]-1beta, IL-6, and tumor necrosis factor [TNF]-alpha) was analyzed by TaqMan real-time reverse transcription-polymerase chain reaction (mRNA) and by ELISA (protein release over 3 hours). Significantly higher levels of IL-1beta, IL-6, MCP-1, and TNF-alpha mRNA and protein were observed in epicardial adipose stores. Proinflammatory properties of epicardial adipose tissue were noted irrespective of clinical variables (diabetes, body mass index, and chronic use of statins or ACE inhibitors/angiotensin II receptor blockers) or plasma concentrations of circulating biomarkers. In a subset of samples (n=11), global gene expression was explored by DNA microarray hybridization and confirmed the presence of a broad inflammatory reaction in epicardial adipose tissue in patients with coronary artery disease. The above findings were paralleled by the presence of inflammatory cell infiltrates in epicardial adipose stores. CONCLUSIONS: Epicardial adipose tissue is a source of several inflammatory mediators in high-risk cardiac patients. Plasma inflammatory biomarkers may not adequately reflect local tissue inflammation. Current therapies do not appear to eliminate local inflammatory signals in epicardial adipose tissue.