Objective To investigate the safety, efficacy of the surgery and the characteristics of the blood flow after coronary artery bypass graft (CABG) surgery using bilateral internal mammary artery (BIMA) to analyze the early operative results, CT results and the graft flow. Methods From December 2015 to July 2016, 52 patients (46 males, 6 females) with an average age of 56.6±6.8 years, underwent CABG using bilateral internal mammary artery. All the operations were carried out under extracorporeal circulation, both internal mammary arteries were obtained with pedicle and the bypass path was designed according to the target vessels. After the anastomosis was completed, the graft flow was measured using Veri Q system. The CT angiography of coronary artery was completed before discharge. Perioperative outcomes, early CT outcomes, and blood flow of grafts were analysed. Results There was no operative mortality. The average operation time was 4.7±0.6 hours, average cardiopulmonary bypass time was 114.8±20.6 minutes, average cross-clamping time was 82.8±17.6 minutes, average mechanical ventilation time was 17.6±10.5 hours and average ICU stay was 2.7±1.8 days. The mean number of distal anastomosis was 4.6±0.8. One patient suffered sternal complication and poor wound healing and then receieved debridement as well as suturing. Other patients discharged without surgical complications. The average flow of left internal mammary artery (LIMA) graft was 28.1±11.4 ml/min with a mean pulsatility index (PI) of 2.2±0.6. The average flow of right internal mammary artery (RIMA) was 27.3±12.0 ml/min with a mean PI of 2.4± 0.8. The mean flow of great saphenous vein was 41.5±21.5 ml/min with a mean PI of 2.2±0.7. There was no significant difference in the mean flow between LIMA and RIMA (P=0.978). The mean flow of the great saphenous vein was significantly higher than that of RIMA and LIMA (P=0.000). CT angiography showed no stenosis. Distal anastomosis of 7 vein grafts and 5 artery grafts was demonstrated shallow in CT angiography and 2 vein grafts were undemonstrated, suggesting occlusion. Conclusion The use of BIMA for CABG is safe with less complications. RIMA flow is equivalent to LIMA flow. RIMA with no stenosis and occlusion of artery grafts in the early stage, therefore is the ideal and stable coronary bypass graft.
Objective To evaluate the risk factors for postoperative in-hospital mortality in elderly patients receiving cardiac valvular surgery, and develop a new prediction models using the least absolute shrinkage and selection operator (LASSO)-logistic regression. Methods The patients≥65 years who underwent cardiac valvular surgery from 2016 to 2018 were collected from the Chinese Cardiac Surgery Registry (CCSR). The patients who received the surgery from January 2016 to June 2018 were allocated to a training set, and the patients who received the surgery from July to December 2018 were allocated to a testing set. The risk factors for postoperative mortality were analyzed and a LASSO-logistic regression prediction model was developed and compared with the EuroSCOREⅡ. Results A total of 7 163 patients were collected in this study, including 3 939 males and 3 224 females, with a mean age of 69.8±4.5 years. There were 5 774 patients in the training set and 1389 patients in the testing set. Overall, the in-hospital mortality was 4.0% (290/7163). The final LASSO-logistic regression model included 7 risk factors: age, preoperative left ventricular ejection fraction, combined coronary artery bypass grafting, creatinine clearance rate, cardiopulmonary bypass time, New York Heart Association cardiac classification. LASSO-logistic regression had a satisfying discrimination and calibration in both training [area under the curve (AUC)=0.785, 0.627] and testing cohorts (AUC=0.739, 0.642), which was superior to EuroSCOREⅡ. Conclusion The mortality rate for elderly patients undergoing cardiac valvular surgery is relatively high. LASSO-logistic regression model can predict the risk of in-hospital mortality in elderly patients receiving cardiac valvular surgery.
Objective To evaluate the safety and efficacy of skeletonized and pedicled harvesting of bilateral internal mammary artery (BIMA) in coronary artery bypass graft (CABG) surgery. Methods From December 2015 to May 2017, 152 patients (128 males, 24 females, age of 56.5±6.8 years) underwent CABG using either skeletonized BIMA (s-BIMA group, n=73) or pedicled BIMA(p-BIMA group, n=79). The operative data and post-operative outcomes were analyzed in the s-BIMA group (61 males, 12 females, age of 56.6±7.0 years) and the p-BIMA group (67 males, 12 females, age of 56.3±6.7 years). Results There was no peri-operative mortality. There was no statistical difference in operative time, cardiopulmonary bypass time, aortic cross-clamp time or internal mammary artery graft flow between the two groups. One patient(1.4%) in the s-BIMA group suffered from severe sternal wound complication, which was major sternal wound complication. Five patients (6.3%) in the p-BIMA group suffered from sternal wound complications, including 1(1.3%) with severe complication and 4(5.1%) with minor complication. One(1.4%) patient in the s-BIMA group and 7 (8.9%) patients in the p-BIMA group suffered from chylothorax. The chest tube drainage significantly reduced in the s-BIMA group, both in postoperative day 1(P=0.000) and postoperative day 1-3 (P=0.001). CT angiography showed no stenosis of BIMA in both groups. Conclusion The use of skeletonized BIMA for CABG is safe and efficacious, with less sternal wound complications, chylothorax and chest tube drainage. Skeletonization should be suggested if BIMA is harvested in CABG.
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.
ObjectiveTo evaluate short-term clinical outcomes of skeletonized bilateral internal mammary artery (sBIMA) in coronary artery bypass grafting (CABG).MethodsThe clinical data of 62 patients (54 males and 8 females with an average age of 56.8±6.0 years) undergoing isolated CABG using sBIMA in our hospital from October 2016 to May 2017 were retrospectively analyzed. The coronary graft flow, perioperative clinical outcomes and CT results were reviewed.ResultsAll the operations were carried out under extracorporeal circulation. Anastomosis of 124 internal mammary arteries was performed and 116 great saphenous veins were used simultaneously with an average anastomosis site of 4.5±0.8 for each patient. The cardiopulmonary bypass time was 116.4±22.9 min, aortic clamping time was 83.0±18.3 min, mechanical ventilation time was 20.8±21.3 h and ICU stay was 2.7±1.7 d. The graft flow of left internal mammary artery (LIMA), right internal mammary artery (RIMA) and great saphenous vein were 28.8±12.4 mL/min, 32.8±13.8 mL/min and 41.5±21.5 mL/min, respectively. There was no significant difference in the graft flow between LIMA and RIMA (P=0.112). There was no perioperative mortality, myocardial infarction or cerebrovascular accident. Only one male patient suffered sternal complication and poor wound healing and then received debridement as well as suturing. Coronary CT angiography showed that distal anastomosis of 7 vein grafts and 5 artery grafts was demonstrated shallow and 1 vein graft was undemonstrated, suggesting occlusion.ConclusionCABG with sBIMA is a safe and reliable technique with excellent early results.
ObjectiveTo analyze the correlation between the gray value of epicardial fat and the prognosis of patients with atrial fibrillation (AF) treated by thoracoscopic radiofrequency ablation.MethodsThe clinical data of 97 patients, including 75 males and 22 females with an average age of 57.8±9.4 years, who underwent thoracoscopic radiofrequency ablation in Fuwai Hospital from 2017 to 2018 were analyzed retrospectively. The left atrial fat volume and average gray scale were calculated by left atrial enhanced CT. According to the average gray scale of left atrial fat tissue, the patients were divided into three groups: a high gray scale group, a medium gray scale group and a low gray scale group. The patients were followed up at 3, 6 and 12 months after operation. The end point of follow-up was the recovery rate of sinus rhythm. Survival analysis was used to analyze the correlation between CT features of epicardial fat enhancement and prognosis.ResultsAfter adjustment of body mass index, body surface area, gender and left atrial end diastolic diameter, regression analysis showed that the fat gray of left atrial enhanced CT was correlated with the type of AF (OR=0.30, 95%CI 0.12-0.79, P=0.014). Cox regression analysis showed that the fat gray value of left atrial CT predicted the recurrence of AF after thoracoscopic radiofrequency ablation (OR=0.92, 95%CI 0.85-0.99). The Kaplan-Meier curve showed significant difference in the long-term recurrence rate of AF among the three groups (P=0.011). The lower left atrial fat enhanced CT gray scale was, the higher long-term recurrence rate of AF was.ConclusionThe gray value of left atrial fat enhanced CT can effectively predict the recurrence of AF after radiofrequency ablation in thoracoscopic surgery.