Long-Term Outcomes of Bioprosthetic and Mechanical Valve Replacement for Patients Aged between 50 and 70 Years.

Background: The choice between bioprosthetic and mechanical valves for aortic valve replacement (AVR) and mitral valve replacement (MVR) among patients aged 50-70 years is controversial. We compared the long-term outcomes of patients using bioprosthetic or mechanical valves to provide clinical evidence for valve selection. Methods: From 2002 to 2007, patients aged 50-70 years who underwent isolated AVR or MVR at the Fuwai Hospital were enrolled. After inverse probability-weighted (IPW) propensity balancing, we evaluated long-term mortality, stroke, and bleeding events between patients receiving mechanical and biological prostheses for MVR or AVR. Results: A total of 1639 patients were included in the study, including 1181 patients undergoing MVR (median follow-up: 11.6 years) and 458 patients undergoing AVR (median follow-up: 11.4 years). After IPW adjustment, there was no significant difference in long-term mortality and stroke rate between patients using bioprosthetic and mechanical valves for MVR [mortality: log-rank p = 0.802; stroke: log-rank p = 0.983] and AVR [mortality: log-rank p = 0.815; stroke: log-rank p = 0.537]. Landmark analysis at 12.5 years yielded significantly lower mortality in the patients receiving mechanical valves compared with bioprosthetic valves in the MVR cohort (p = 0.028). Patients receiving mechanical aortic valves displayed an increased risk of bleeding compared with those who received bioprosthetic aortic valves [Hazard Ratio (95% Confidence interval): 2.51 (1.06-5.93) p = 0.036]. Conclusions: For patients aged 50-70, there was no significant difference in overall long-term mortality between mechanical and bioprosthetic valve recipients. Patients receiving mechanical valves for MVR displayed lower mortality after 12.5 years follow-up. For AVR, bioprosthetic valves were associated with a lower risk of bleeding.

Association between stress hyperglycaemia and in-hospital cardiac events after coronary artery bypass grafting in patients without diabetes: A retrospective observational study of 5450 patients.

AIMS: To investigate the impact of stress hyperglycaemia (SH) on in-hospital adverse cardiac events after coronary artery bypass grafting (CABG) in patients without diabetes. MATERIALS AND METHODS: In total, 5450 patients without diabetes who underwent CABG were analysed. SH was defined as any two instances in which the random blood glucose level was >7.8 mmol/L after CABG in the intensive care unit (ICU). The primary outcome was major adverse cardiac events (MACEs), including in-hospital mortality, acute myocardial infarction, stroke and acute renal failure. Secondary outcomes included surgical site infection (SSI) and length of ICU stay. RESULTS: Patients with SH had higher rates of MACEs (5.7% vs. 2.3%, p < .0001) and higher SSI (3.3% vs. 1.4%, p = .0003) and longer ICU stays (2.6 ± 2.0 vs. 1.3 ± 1.3 days, p < .0001) than those without SH. Furthermore, SH was associated with a higher risk of MACEs [odds ratio (OR): 2.32, 95% confidence interval (CI): 1.38-3.90], SSI (OR: 2.21, 95% CI: 1.20-3.95) and longer ICU stay (OR: 12.27, 95% CI: 9.41-16.92) after adjusting for confounders. Subgroup analysis showed that patients with SH >10 mmol/L or SH that occurred in the ICU and lasted more than 48 h had increased risks of postoperative complications (p < .05). CONCLUSIONS: SH was significantly associated with an increased risk of MACEs, SSI and longer ICU stay after CABG in patients without diabetes. In addition, SH >10 mmol/L or that occurred in the ICU and lasted more than 48 h increased the risk of adverse outcomes.

In Situ Deposition of Skin-Adhesive Liquid Metal Particles with Robust Wear Resistance for Epidermal Electronics.

Comfort and mechanical stability are vital for epidermal electronics in daily use. In situ deposition of circuitry without the protection of substrates or encapsulation can produce imperceptible, conformal, and permeable epidermal electronics. However, they are easily destroyed by daily wear because the binding force between deposited materials and skin is usually weak. Here, we in situ deposited skin-adhesive liquid metal particles (ALMP) to fabricate epidermal electronics with robust wear resistance. It represents the most wear-resistant in situ deposited epidermal electronic materials. It can withstand ∼1600 cm, 175 g loaded paper tape wearing by a standard abrasion wear tester. Stretchability, conformality, permeability, and thinness of the ALMP coating provide an imperceptible and comfortable wearing experience. Without degradation of electrical property caused by solvent evaporation, the dry ALMP coating possesses natural advantages over gel electrodes. In situ deposited ALMP is an ideal material for fabricating comfortable epidermal electronics.

No-Touch Versus Conventional Vein Harvesting Techniques at 12 Months After Coronary Artery Bypass Grafting Surgery: Multicenter Randomized, Controlled Trial.

BACKGROUND: Vein graft occlusion is deemed a major challenge in coronary artery bypass grafting. Previous studies implied that the no-touch technique for vein graft harvesting could reduce occlusion rate compared with the conventional approach; however, evidence on the clinical benefit and generalizability of the no-touch technique is scare. METHODS: From April 2017 to June 2019, we randomly assigned 2655 patients undergoing coronary artery bypass grafting at 7 hospitals in a 1:1 ratio to receive no-touch technique or conventional approach for vein harvesting. The primary outcome was vein graft occlusion on computed tomography angiography at 3 months and the secondary outcomes included 12-month vein graft occlusion, recurrence of angina, and major adverse cardiac and cerebrovascular events. The generalized estimate equation model was used to account for the cluster effect of grafts from the same patient. RESULTS: During the follow-up, 2533 (96.0%) participants received computed tomography angiography at 3 months after coronary artery bypass grafting and 2434 (92.2%) received it at 12 months. The no-touch group had significantly lower rates of vein graft occlusion than the conventional group both at 3 months (2.8% versus 4.8%; odds ratio, 0.57 [95% CI, 0.41-0.80]; P<0.001) and 12 months (3.7% versus 6.5%; odds ratio, 0.56 [95% CI, 0.41-0.76]; P<0.001). Recurrence of angina was also less common in the no-touch group at 12 months (2.3% versus 4.1%; odds ratio, 0.55 [95% CI, 0.35-0.85]; P<0.01). Rates of major adverse cardiac and cerebrovascular events were of no significant difference between the 2 groups. The no-touch technique was associated with higher rates of leg wound surgical interventions at 3-month follow-up (10.3% versus 4.3%; odds ratio, 2.55 [95% CI, 1.85-3.52]; P<0.001). CONCLUSIONS: Compared with the conventional vein harvesting approach in coronary artery bypass grafting, the no-touch technique significantly reduced the risk of vein graft occlusion and improved patient prognosis. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03126409.

Effect of High- vs Low-Dose Tranexamic Acid Infusion on Need for Red Blood Cell Transfusion and Adverse Events in Patients Undergoing Cardiac Surgery: The OPTIMAL Randomized Clinical Trial.

Importance: Tranexamic acid is recommended for reducing blood loss and transfusion in cardiac surgery. However, it remains unknown whether a high dose of tranexamic acid provides better blood-sparing effect than a low dose without increasing the risk of thrombotic complications or seizures in cardiac surgery. Objective: To compare the efficacy and adverse events of high-dose vs low-dose tranexamic acid in patients undergoing cardiac surgery with cardiopulmonary bypass. Design, Setting, and Participants: Multicenter, double-blind, randomized clinical trial among adult patients undergoing cardiac surgery with cardiopulmonary bypass. The study enrolled 3079 patients at 4 hospitals in China from December 26, 2018, to April 21, 2021; final follow-up was on May 21, 2021. Interventions: Participants received either a high-dose tranexamic acid regimen comprising a 30-mg/kg bolus, a 16-mg/kg/h maintenance dose, and a 2-mg/kg prime (n = 1525) or a low-dose regimen comprising a 10-mg/kg bolus, a 2-mg/kg/h maintenance dose, and a 1-mg/kg prime (n = 1506). Main Outcomes and Measures: The primary efficacy end point was the rate of allogeneic red blood cell transfusion after start of operation (superiority hypothesis), and the primary safety end point was a composite of the 30-day postoperative rate of mortality, seizure, kidney dysfunction (stage 2 or 3 Kidney Disease: Improving Global Outcomes [KDIGO] criteria), and thrombotic events (myocardial infarction, ischemic stroke, deep vein thrombosis, and pulmonary embolism) (noninferiority hypothesis with a margin of 5%). There were 15 secondary end points, including the individual components of the primary safety end point. Results: Among 3079 patients who were randomized to treatment groups (mean age, 52.8 years; 38.1% women), 3031 (98.4%) completed the trial. Allogeneic red blood cell transfusion occurred in 333 of 1525 patients (21.8%) in the high-dose group and 391 of 1506 patients (26.0%) in the low-dose group (risk difference [RD], -4.1% [1-sided 97.55% CI, -∞ to -1.1%]; relative risk, 0.84 [1-sided 97.55% CI, -∞ to 0.96; P = .004]). The composite of postoperative seizure, thrombotic events, kidney dysfunction, and death occurred in 265 patients in the high-dose group (17.6%) and 249 patients in the low-dose group (16.8%) (RD, 0.8%; 1-sided 97.55% CI, -∞ to 3.9%; P = .003 for noninferiority). Fourteen of the 15 prespecified secondary end points were not significantly different between groups, including seizure, which occurred in 15 patients (1.0%) in the high-dose group and 6 patients (0.4%) in the low-dose group (RD, 0.6%; 95% CI, -0.0% to 1.2%; P = .05). Conclusions and Relevance: Among patients who underwent cardiac surgery with cardiopulmonary bypass, high-dose compared with low-dose tranexamic acid infusion resulted in a modest statistically significant reduction in the proportion of patients who received allogeneic red blood cell transfusion and met criteria for noninferiority with respect to a composite primary safety end point consisting of 30-day mortality, seizure, kidney dysfunction, and thrombotic events. Trial Registration: ClinicalTrials.gov Identifier: NCT03782350.

Risk Factors for Aortic Regurgitation Progression After Repair of Sinus of Valsalva Aneurysm.

BACKGROUND: The main treatment for a ruptured sinus of Valsalva aneurysm (SVA) is surgical repair. Postoperative progression of aortic regurgitation (AR) following SVA repair increases the risk of reoperation, which decreases the long-term survival. Thus, identifying the risk factors for postoperative AR progression is of great significance. METHODS: Adult patients who were diagnosed with ruptured SVA and underwent surgical repair at the current centre were reviewed. Necessary data in the institutional database were extracted. The perioperative and follow-up assessments of the aortic valve by transthoracic echocardiography were also obtained. The aortic regurgitation progression was grouped into three categories: newly developing, recurrence, and worsening. Sixteen (16) variables were screened to identify potential risk factors by univariate logistic regression analysis or Chi-squared test. Variables with p-values <0.1 were further analysed by multivariate logistic regression models to find independent risk factors. RESULTS: A total of 198 consecutive patients from June 2006 to January 2018 were included. The overall incidence of postoperative AR progression was 19.2% (38 of 198). After the univariate analysis, SVA originating from the right coronary sinus, coexisting with ventricular septal defect, larger diameter of aortic annulus, and larger cardiothoracic ratio were screened as potential risk factors. Multivariate analysis indicated that coexisting with a ventricular septal defect (VSD) (OR, 2.82; 95% CI, 1.217-6.532; p=0.016) and larger cardiothoracic ratio (OR, 1.061; 95% CI, 1.001-1.124; p=0.047) were independent risk factors for postoperative AR progression. CONCLUSIONS: To prevent postoperative AR progression after surgical repair, more careful inspection and appropriate surgical techniques are necessary for patients coexisting with VSD or with a larger cardiothoracic ratio.

Comparison of clinical results between percutaneous closure and surgical repair of ruptured sinus of Valsalva aneurysm.

OBJECTIVES: This study was conducted to investigate whether percutaneous closure of ruptured sinus of Valsalva aneurysm (SVA) is as safe and effective as surgery repair. BACKGROUND: Percutaneous closure of ruptured SVA has been becoming an alternative to the traditional surgical repair recently. The reports regarding direct comparison of these two treatment options are scarce. METHODS: The medical records from the institutional database were retrospectively analyzed. A total of 134 patients were reviewed, including 26 patients undergoing percutaneous closure and 108 patients being treated surgically. To reduce the potential bias, 32 patients from Surgical Repair group were selected by propensity score matching. RESULTS: All the ruptured SVAs were successfully closed in each group. No severe procedure-related complications were found in the perioperative period. After matching, there were no significant differences in the baseline clinical characteristics. The median postoperative hospital stays of Matched group were significantly longer than that of Percutaneous Closure group (7 days vs. 1 day, p < .001). Aortic regurgitation, residual shunt and recurrence of SVAs were common complications in both Percutaneous Closure group and Surgical Repair group. CONCLUSIONS: The appropriately selected patients with ruptured SVA could be treated by percutaneous closure with an acceptable risk of short-term complications. Though surgical repair remains the main treatment option for ruptured SVAs, percutaneous closure could be considered in patients with a small-size rupture and no associated cardiac abnormalities.

Outcome impact of different tranexamic acid regimens in cardiac surgery with cardiopulmonary bypass (OPTIMAL): Rationale, design, and study protocol of a multicenter randomized controlled trial.

Tranexamic acid (TxA) reduces perioperative blood transfusion in cardiac surgery; however, the optimal dose of TxA remains unknown. METHODS AND RESULTS: This large-scale, double-blind, randomized controlled trial with a 1-year follow-up enrolls patients undergoing elective cardiac surgery with cardiopulmonary bypass. Patients are randomly assigned 1:1 into either the high-dose TxA group (intravenous bolus [30 mg/kg] after anesthesia followed by intravenous maintenance [16 mg/kg/h] throughout the operation, and a pump prime dose of 2 mg/kg) or the low-dose TxA group (intravenous bolus and maintenance are 10 mg/kg and 2 mg/kg/h, respectively, and a pump prime dose of 1 mg/kg). The primary efficacy end point is the rate of perioperative allogeneic red blood cell (RBC) transfusion defined as the number (%) of patients who will receive at least 1 RBC unit from operation day to discharge. The primary safety end point is the 30-day rate of the composite of perioperative seizures, renal dysfunction, myocardial infarction, ischemic stroke, deep vein thrombosis, pulmonary embolism, and all-cause mortality. The secondary end points are perioperative allogeneic RBC transfusion volume, the non-RBC blood transfusion rate, postoperative bleeding, reoperation rate, mechanical ventilation duration, intensive care unit stay, hospital length of stay, total hospitalization cost, each component of composite primary safety end point, and the 6-month/1-year follow-up mortality and morbidity. We estimated a sample size of 3,008 participants. CONCLUSIONS: The study is designed to identify a TxA dose with maximal efficacy and minimal complications. We hypothesize that the high dose has superior efficacy and noninferior safety to the low dose.

A novel nomogram to predict perioperative acute kidney injury following isolated coronary artery bypass grafting surgery with impaired left ventricular ejection fraction.

BACKGROUND AND OBJECTIVE: Heart failure (HF) is a global health issue, and coronary artery bypass graft (CABG) is one of the most effective surgical treatments for HF with coronary artery disease. Unfortunately, the incidence of postoperative acute kidney injury (AKI) is high in HF patients following CABG, and there are few tools to predict AKI after CABG surgery for such patients. The aim of this study is to establish a nomogram to predict the incidence of AKI after CABG in patients with impaired left ventricular ejection fraction (LVEF). METHODS: From 2012 to 2017, Clinical information of 1208 consecutive patients who had LVEF< 50% and underwent isolated CABG was collected to establish a derivation cohort. A novel nomogram was developed using the logistic regression model to predict postoperative AKI among these patients. According to the same inclusion criteria and the same period, we extracted the data of patients from 6 other large cardiac centers in China (n = 540) from the China Heart Failure Surgery Registry (China-HFSR) database for external validation of the new model. The nomogram was compared with 3 other available models predicting renal failure after cardiac surgery in terms of calibration, discrimination and net benefit. RESULTS: In the derivation cohort (n = 1208), 90 (7.45%) patients were diagnosed with postoperative AKI. The nomogram included 7 independent risk factors: female, increased preoperative creatinine(> 2 mg/dL), LVEF< 35%, previous myocardial infarction (MI), hypertension, cardiopulmonary bypass(CPB) used and perioperative blood transfusion. The area under the receiver operating characteristic curve (AUC) was 0.738, higher than the other 3 models. By comparing calibration curves and decision curve analyses (DCA) with other models, the novel nomogram showed better calibration and greater net benefit. Among the 540 patients in the validation cohort, 104 (19.3%) had postoperative AKI, and the novel nomogram performed better with respect to calibration, discrimination and net benefit. CONCLUSIONS: The novel nomogram is a reliable model to predict postoperative AKI following isolated CABG for patients with impaired LVEF.

Surgical results and pathological analysis of cardiac fibroma in the adolescent and the adult.

BACKGROUNDS: Disparities may exist between the adolescent and the adult patients with cardiac fibromas in the symptoms, surgical outcomes, and pathological characteristics. The aim of this study was to compare short and midterm surgical outcomes of cardiac fibromas and to compare the biomarker expressions of tumor tissue samples between the adult and the adolescent. METHODS: Consecutive patients with the diagnosis of cardiac fibroma were admitted and received surgeries. Primary outcomes included in-hospital mortality, low cardiac output, and readmission due to heart failure. The expression of PCNA and Ki67, two widely adopted indicators of cell proliferation, were evaluated in tissue samples. RESULTS: A total of five adolescent patients and five adult patients diagnosed as cardiac fibroma were admitted and given surgeries. When compare with the adults, the adolescent patients were more likely to present symptoms on admission (P = .048). Postoperative low cardiac output syndrome was significantly higher in the adolescents than in the adults (80.0% vs 0.0, P = .048). The tumor volume relative to ventricular end diastolic diameter had good discriminative ability for low cardiac output (c statistics: 0.96). Pathologically, the percentage of PCNA-positive cell nuclei was significantly higher in the adolescents than in the adults (36.04% ± 10.54% vs 4.15% ± 3.93%, P = .001). However, there were no Ki67-positive nuclei in the 10 cases. CONCLUSIONS: In the current study, we found that postoperative low cardiac output was more likely to occur in the adolescent patients than in the adult patients. When compared with the adult patients, significantly more PCNA-positive nuclei were observed in the adolescents.

A Novel Risk Stratification System for Predicting In-Hospital Mortality Following Coronary Artery Bypass Grafting Surgery with Impaired Left Ventricular Ejection Fraction.

BACKGROUND: Coronary artery disease (CAD) is the most common cause of heart failure (HF), and impaired ejection fraction (EF<50%) is a crucial precursor to HF. Coronary artery bypass grafting (CABG) is an effective surgical solution to CAD-related HF. In light of the high risk of cardiac surgery, appropriate scores for groups of patients are of great importance. We aimed to establish a novel score to predict in-hospital mortality for impaired EF patients undergoing CABG. METHODS: Clinical information of 1,976 consecutive CABG patients with EF<50% was collected from January 2012 to December 2017. A novel system was developed using the logistic regression model to predict in-hospital mortality among patients with EF<50% who were to undergo CABG. The scoring system was named PGLANCE, which is short for seven identified risk factors, including previous cardiac surgery, gender, load of surgery, aortic surgery, NYHA stage, creatinine, and EF. AUC statistic was used to test discrimination of the model, and the calibration of this model was assessed by the Hosmer-lemeshow (HL) statistic. We also evaluated the applicability of PGLANCE to predict in-hospital mortality by comparing the 95% CI of expected mortality to the observed one. Results were compared with the European Risk System in Cardiac Operations (EuroSCORE), EuroSCORE II, and Sino System for Coronary Operative Risk Evaluation (SinoSCORE). RESULTS: By comparing with EuroSCORE, EuroSCORE II and SinoSCORE, PGLANCE was well calibrated (HL P = 0.311) and demonstrated powerful discrimination (AUC=0.846) in prediction of in-hospital mortality among impaired EF CABG patients. Furthermore, the 95% CI of mortality estimated by PGLANCE was closest to the observed value. CONCLUSION: PGLANCE is better with predicting in-hospital mortality than EuroSCORE, EuroSCORE II, and SinoSCORE for Chinese impaired EF CABG patients.

Surgical treatment of left ventricular fibroma in adult: case report and literature review.

Cardiac fibroma is a rare benign primary tumour of the heart. In the paediatric population, it has been reported as the second most common benign cardiac tumour following rhabdomyoma. However, the prevalence of cardiac fibroma is rarely reported in the adult population. Signs and symptoms are nonspecific, including palpitations, cardiac murmur, arrhythmias, dyspnoea, cyanosis, chest pain, and sudden mortality, whereas, a number of patients with cardiac fibroma are asymptomatic. Surgical resection should be considered as the best option in symptomatic patients. This study reported four surgical cases of adults with cardiac fibroma arising from the left ventricle and a literature review regarding the clinical and pathological features, diagnostic modalities, therapeutic aspects, and prognosis of this rare entity.

A tissue-based simulation model for cardiopulmonary bypass cannulation/decannulation training.

BACKGROUND: Cardiopulmonary bypass is the basis of open heart surgery. Through simulation-based learning, residents may receive structured training of cardiopulmonary bypass techniques. Therefore, we built a high-fidelity, tissue-based simulation model for cardiopulmonary bypass cannulation/decannulation training. METHODS: The core of the model is a whole block of cadaveric animal heart and lung. The discarded membrane oxygenators are used as blood reservoirs. The tubing and suckers recycled from animal experiments are washed and reused. To set up the model, the cadaveric heart and lung are placed into a container of appropriate size. The "arterial" tubing is connected with a pressure gauge, the distal aorta, the superior vena cava, and arterial cannula, respectively. The "venous" tubing is composed of three independent catheters, respectively, for the practice of venous cannulation, for the connection of sucker and for the practice of placing left atrial/ventricular vent. All tubes are installed on the roller pumps to maintain the correct flow direction. A technician should be responsible for operating the heart-lung machine, clamping and releasing the specific segments of tubing, adjusting the pressure, and cooperating with the trainees to practice. RESULTS: Using the simulation model, 18 residents underwent cardiopulmonary bypass techniques training, with an average satisfaction of 8.94 points. The mean score on the overall fidelity of the simulation model assessed by nine experienced cardiothoracic surgeons was 8.67 points. CONCLUSION: The tissue-based simulation model has a certain degree of realism. Cardiac surgery residents can practice necessary cardiopulmonary bypass cannulation/decannulation techniques by this model.

Mid-Term Outcome for Anomalous Origin of the Left Coronary Artery From the Pulmonary Artery.

BACKGROUND: This study is a single-centre experience with surgical intervention of anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA). METHODS: A retrospective review was performed of patients who underwent ALCAPA repair between November 1991 and October 2017. RESULTS: A total of 138 patients with a median age of 36 months underwent ALCAPA repair. The median follow-up period was 3.5 years. Overall, 114 (82.6%) patients received coronary reimplantation, 21 (15.2%) underwent Takeuchi repair, and three (2.1%) were treated by closure of the ALCAPA plus coronary artery bypass graft. Concomitant mitral repair was performed in 50 patients with moderate-to-severe mitral regurgitation (MR). Three (2.1%) patients died in hospital. Three (2.1%) patients needed extracorporeal membrane oxygenation (ECMO) support. Seven (5.0%) patients needed delayed sternal closure. In patients with decreased preoperative left ventricular ejection fraction (LVEF) (<50%), the LVEF significantly improved from 25% to 33% at discharge (p = 0.001). The percentage of more than moderately significant MR decreased from 36.2% to 5.2% (p = 0.02). There was no late mortality. Two patients needed reoperation because of baffle leaks after Takeuchi repair. Three patients had severe MR. All patients had normal LVEF at last follow-up. The median normalisation time of left ventricular function was 6 months. CONCLUSIONS: Short-term and mid-term outcomes of surgical treatment for ALCAPA patients were excellent. The concomitant mitral valve repair did not increase the perioperative risk but had satisfactory mid-term outcomes. Normalisation of left ventricular function is expected within the first 6 months.

Intravenous Iron Versus Placebo in the Management of Postoperative Functional Iron Deficiency Anemia in Patients Undergoing Cardiac Valvular Surgery: A Prospective, Single-Blinded, Randomized Controlled Trial.

OBJECTIVE: To compare the efficacy of intravenous iron versus placebo to correct postoperative functional iron deficiency anemia in patients undergoing cardiac valvular surgery. DESIGN: A prospective, single-blinded, randomized controlled study. SETTING: National Center for Cardiovascular Diseases and a university hospital. PARTICIPANTS: The study comprised 150 patients with postoperative functional iron deficiency anemia after cardiac valvular surgery. INTERVENTIONS: The patients were randomly assigned (1:1) to either the treatment (intravenous iron) group or the control (placebo) group. MEASUREMENTS AND MAIN RESULTS: The hemoglobin and ferritin concentrations and postoperative adverse events were collected and compared between the 2 groups. The hemoglobin concentration and the proportion of patients who had their anemia corrected or achieved hemoglobin increments of >20 g/L in the intravenous iron group were significantly higher than that in the placebo group at postoperative day 14 (p = 0.023, p = 0.037, and p = 0.001), whereas there was no statistical difference at postoperative day 7. The ferritin concentration was substantially higher at postoperative day 7 and postoperative day 14 in the intravenous iron group compared with the placebo group (both p < 0.001). There were no significant differences in rates of death, blood tranfusion, antibiotic upgrade, ventilator time >24 hours, postoperative hospital stay >10 days, poor wound healing, and perivalvular leakage between the 2 groups. CONCLUSIONS: Intravenous iron could significantly increase the hemoglobin level in patients with postoperative functional iron deficiency anemia at postoperative day 14. However, there is no difference in blood transfusion requirements or postoperative adverse outcomes between the 2 groups.

An exploration of the surgical skill training curriculum for cardiac surgery residents.

BACKGROUND: A "boot camp" program is commonly adopted in surgical skills training. Due to a shortage of cardiac surgeons, establishment of a well-designed training curriculum for cardiac surgery residents is needed in developing countries. METHODS: We established a comprehensive 3-module training curriculum, including: (1) the cardiopulmonary bypass establishment technique, (2) coronary artery anastomosis and (3) basic surgical skills of thoracoscopy. Each module was designed for one technique, with a training time of 1 week. Each module included theoretical knowledge learning, demonstration by senior surgeons, and practice through simulators and in vivo animal experiment. A series of questionnaires were used to assess the training effect. RESULTS: We organized 50 person-times of training. The overall satisfaction of residents participating in the entire 3-module training was 7.88 points (from a full score of 10 points). The satisfaction of each module was 8.94, 8.13, and 7.63, respectively. The survey suggested the training could increase trainees' confidence in the operation (P < 0.05). Some trainees also proposed some suggestions for the further improvement of the curriculum. CONCLUSIONS: It is feasible to develop a multimodule comprehensive surgical skill training curriculum for cardiac surgery residents in China, whose confidence can be effectively enhanced.

Can red blood cell distribution width predict long-term cardiovascular event after off-pump coronary artery bypass? A retrospective study.

INTRODUCTION: The effect of red blood cell distribution width (RDW) on long-term major cardiac and cardiovascular event (MACCE) in patients with off-pump coronary artery bypass (OPCAB) has not been adequately studied. We investigated the relationship between RDW and the risk of MACCE in patients who underwent OPCAB. METHODS: We retrospectively analyzed the data of 440 consecutive, nonanemic patients (362 males; 82.27% and mean age 60.8 ± 8.9 years) who underwent OPCAB between October 2009 and September 2012 in Fuwai Hospital. Long-term follow-up was obtained through phone calls, hospital records, and clinic visits. MACCE (death, ST elevated infarction, repeat coronary revascularization, stroke) was determined. RESULTS: Over a median of 7.0-year follow-up, 80 incident MACCE events were identified. The RDW levels on admission were significantly higher in MACCE group than non-MACCE group (13.1 ± 0.7 vs 12.8 ± 0.7; P = .005). Using the Cox proportional hazards models, we found that per 1% increment of RDW, the incident of MACCE was increased in different models (hazard ratio [HR] was 1.520, 1.532, and 1.795, respectively; P = .002, .004, and .002). The receiver-operating characteristic analysis revealed an RDW cut-off value of 13% predicting MACCE. Therefore, patients were grouped on this cut-off value. The Kaplan-Meier plot revealed significantly lower event-free survival in the higher RDW group (P = .0158). Compared with subjects in the RDW <13% in full model, subjects in the RDW ≥13% had an HR of 1.829 (95% confidence interval, 1.103-3.032; P = .019). CONCLUSIONS: An RDW level greater than 13% in hospital admission is independently associated with an increased incidence of long-term MACCE after OPCAB.

[Design of an axial blood pump of diffuser with splitter blades and cantilevered main blades].

An implantable axial blood pump was designed according to the circulation assist requirement of severe heart failure patients of China. The design point was chosen at 3 L/min flow rate with 100 mm Hg pressure rise when the blood pump can provide flow rates of 2-7 L/min. The blood pump with good hemolytic and anti-thrombogenic property at widely operating range was designed by developing a structure that including the spindly rotor impeller structure and the diffuser with splitter blades and cantilevered main blades. Numerical simulation and particle image velocimetry (PIV) experiment were conducted to analyze the hydraulic, flow fields and hemolytic performance of the blood pump. The results showed that the blood pump could provide flow rates of 2-7 L/min with pressure rise of 60.0-151.3 mm Hg when the blood pump rotating from 7 000 to 11 000 r/min. After adding the splitter blades, the separation flow at the suction surface of the diffuser has been reduced efficiently. The cantilever structure changed the blade gap from shroud to hub that reduced the tangential velocity from 6.2 m/s to 4.3-1.1 m/s in blade gap. Moreover, the maximum scalar shear stress of the blood pump was 897.3 Pa, and the averaged scalar shear stress was 37.7 Pa. The hemolysis index of the blood pump was 0.168% calculated with Heuser's hemolysis model. The PIV and simulated results showed the overall agreement of flow field distribution in diffuser region. The blood damage caused by higher shear stress would be reduced by adopting the spindle rotor impeller and diffuser with splitter blades and cantilevered main blades. The blood could flow smoothly through the axial blood pump with satisfactory hydraulics performance and without separation flow.

Effects of Cone-Shaped Bend Inlet Cannulas of an Axial Blood Pump on Thrombus Formation: An Experiment and Simulation Study.

BACKGROUND Cannula shape and connection style influence the risk of thrombus formation in the blood pump by varying the blood flow characteristics inside the pump. Inlet cannulas should be designed based on the need for anatomical fit and reducing the risk of thrombus generation in the blood pump. The effects on thrombus formation of the cone-shaped bend inlet cannulas of axial blood pumps should be studied. MATERIAL AND METHODS The cannulas were designed as cone-shaped, with 1 bent section connecting 2 straight sections. Both the silicone tube and novel cone-shaped cannula were simulated for comparison. The flow fields of a blood pump with inlet cannula were simulated by computational fluid dynamics (CFD) at flows of 2.0, 2.5, and 3.0 liters per minute (lpm), with pump rotational speeds of 7500, 8000, and 8500 rpm, respectively. Then, 6 two-dimensional (2D) particle image velocimetry (PIV) tests were conducted and the velocity distributions were analyzed. RESULTS A low-velocity region was located inside the pump entrance when a soft silicone tube was used. At 8500 rpm and 3.0 lpm working condition, the minimum velocity inside the pump with cone-shaped cannulas was 2.5×10^-1 m/s. The cone-shaped cannulas eliminated the low-velocity region inside the pump. Both CFD and PIV results showed that the low-velocity region did not spread to the entrance of the blood pump within the flow range from 2.0 lpm to 7.0 lpm. CONCLUSIONS The designed cone-shaped bent cannulas can eliminate the low-velocity region inside the blood pump and reduce the risk of thrombus formation in the blood pump.

Efficacy of Long-Term ß-Blocker Therapy for Secondary Prevention of Long-Term Outcomes After Coronary Artery Bypass Grafting Surgery.

BACKGROUND: Conflicting results from recent observational studies have raised questions concerning the benefit of ß-blockers for patients undergoing coronary artery bypass grafting (CABG). Furthermore, the efficacy of long-term ß-blocker therapy in CABG patients after hospital discharge is uncertain. METHODS AND RESULTS: The study included 5926 consecutive patients who underwent CABG and were discharged alive. The prevalence and consistency of ß-blocker use were determined in patients with and without a history of myocardial infarction (MI). ß-Blockers were always used in 1280 patients (50.9%) with and 1642 patients (48.1%) without previous MI after CABG. Compared with always users (n=2922, 49.3%), the risk of all-cause death was significantly higher among inconsistent ß-blocker users (hazard ratio [HR], 1.96; 95% confidence interval [CI], 1.50-2.57), and never using ß-blockers was associated with increased risk of both all-cause death (HR, 1.42; 95% CI, 1.01-2.00) and the composite of adverse cardiovascular events (HR, 1.29; 95% CI, 1.10-1.50). In the cohort without MI, the HR for all-cause death was 1.70 (95% CI, 1.17-2.48) in inconsistent users and 1.23 (95% CI, 0.76-1.99) in never users. In the MI cohort, mortality was higher for inconsistent users (HR, 2.14; 95% CI, 1.43-3.20) and for never users (HR, 1.59; 95% CI, 1.07-2.63). Consistent results were obtained in equivalent sensitivity analyses. CONCLUSIONS: In patients with or without previous MI undergoing CABG, the consistent use of ß-blockers was associated with a lower risk of long-term mortality and adverse cardiovascular events. Strategies should be developed to understand and improve discharge prescription of ß-blockers and long-term patient adherence.