Objective To evaluate the safety and efficacy of transcatheter mitral valve-in-valve replacement(ViV-TMVR)in the treatment of bioprosthetic mitral valve failure.Methods Seventeen patients with bioprosthetic mitral valve failure who required ViV-TMVR were selected.Preoperative data including age,gender,body mass index(BMI),usage time of bioprosthetic mitral valve,comorbidities(hypertension,coronary heart disease,old cerebral infarction,atrial fibrillation and diabetes)and New York Heart Association(NYHA)functional class were recorded,and left ventricular end-diastolic diameter(LVEDD),right atrial diameter(RA),pulmonary artery systolic pressure(PASP),left ventricular ejection fraction(LVEF),type of bioprosthetic mitral valve failure,degree of bioprosthetic mitral valve regurgitation and stenosis,peak velocity and mean transvalvular pressure gradient of the bioprosthetic mitral valve,and Society of Thoracic Surgeons(STS)score were also collected.Intraoperative data included puncture route,valve type,intraoperative complications,operation time and immediate postoperative transesophageal echocardiography(TEE)assessment(peak velocity and mean transvalvular pressure gradient of the valve-in-valve,valve-in-valve regurgitation or paravalvular regurgitation)were collected.Postoperative data included time in the intensive care unit(ICU)/cardiovascular intensive care unit(CCU),total postoperative hospital stay and 30-day postoperative echocardiographic results and NYHA functional class were recorded.Patients were divided into the domestic NewMed valve group(10 cases)and the imported Edwards valve group(7 cases)based on the type of valve used.The safety and efficacy of ViV-TMVR were analyzed,and the efficacy of domestic valves and imported valves was compared.Results All 17 patients successfully underwent ViV-TMVR via the transseptal approach without serious complications,and the 30-day readmission rate was 0%.There were no significant differences in operation time of domestic valves and imported valves,mild paravalvular regurgitation of the valve-in-valve,peak velocity and mean transvalvular pressure gradient of the valve-in-valve immediately after surgery and at 30-day postoperatively,time in ICU/CCU,total postoperative hospital stay and the proportion of patients with NYHA functional class Ⅲ-Ⅳ at 30-day postoperatively between the domestic valve group and the imported valve group.During the 30-day follow-up,one patient died of cerebral hemorrhage,and one patient had major adverse cardiovascular events(MACE,cerebral hemorrhage).Compared with before the operation,the peak velocity and mean transvalvular pressure gradient of the valve-in-valve,LVEF,and PASP decreased immediately after surgery and at 30 days after surgery.Compared with immediately after surgery,the peak velocity and mean transvalvular pressure gradient of the valve-in-valve increased at 30 days postoperatively(P＜0.01),while there were no significant differences in LVEF and PASP.Conclusion Transseptal ViV-TMVR is safe and effective in the short term for patients with bioprosthetic mitral valve failure who are at high risk of re-thoracotomy,and the efficacy of domestic valves is comparable to that of imported valves.

Objective To evaluate the safety and efficacy of transcatheter mitral valve-in-valve replacement(ViV-TMVR)in the treatment of bioprosthetic mitral valve failure.Methods Seventeen patients with bioprosthetic mitral valve failure who required ViV-TMVR were selected.Preoperative data including age,gender,body mass index(BMI),usage time of bioprosthetic mitral valve,comorbidities(hypertension,coronary heart disease,old cerebral infarction,atrial fibrillation and diabetes)and New York Heart Association(NYHA)functional class were recorded,and left ventricular end-diastolic diameter(LVEDD),right atrial diameter(RA),pulmonary artery systolic pressure(PASP),left ventricular ejection fraction(LVEF),type of bioprosthetic mitral valve failure,degree of bioprosthetic mitral valve regurgitation and stenosis,peak velocity and mean transvalvular pressure gradient of the bioprosthetic mitral valve,and Society of Thoracic Surgeons(STS)score were also collected.Intraoperative data included puncture route,valve type,intraoperative complications,operation time and immediate postoperative transesophageal echocardiography(TEE)assessment(peak velocity and mean transvalvular pressure gradient of the valve-in-valve,valve-in-valve regurgitation or paravalvular regurgitation)were collected.Postoperative data included time in the intensive care unit(ICU)/cardiovascular intensive care unit(CCU),total postoperative hospital stay and 30-day postoperative echocardiographic results and NYHA functional class were recorded.Patients were divided into the domestic NewMed valve group(10 cases)and the imported Edwards valve group(7 cases)based on the type of valve used.The safety and efficacy of ViV-TMVR were analyzed,and the efficacy of domestic valves and imported valves was compared.Results All 17 patients successfully underwent ViV-TMVR via the transseptal approach without serious complications,and the 30-day readmission rate was 0%.There were no significant differences in operation time of domestic valves and imported valves,mild paravalvular regurgitation of the valve-in-valve,peak velocity and mean transvalvular pressure gradient of the valve-in-valve immediately after surgery and at 30-day postoperatively,time in ICU/CCU,total postoperative hospital stay and the proportion of patients with NYHA functional class Ⅲ-Ⅳ at 30-day postoperatively between the domestic valve group and the imported valve group.During the 30-day follow-up,one patient died of cerebral hemorrhage,and one patient had major adverse cardiovascular events(MACE,cerebral hemorrhage).Compared with before the operation,the peak velocity and mean transvalvular pressure gradient of the valve-in-valve,LVEF,and PASP decreased immediately after surgery and at 30 days after surgery.Compared with immediately after surgery,the peak velocity and mean transvalvular pressure gradient of the valve-in-valve increased at 30 days postoperatively(P＜0.01),while there were no significant differences in LVEF and PASP.Conclusion Transseptal ViV-TMVR is safe and effective in the short term for patients with bioprosthetic mitral valve failure who are at high risk of re-thoracotomy,and the efficacy of domestic valves is comparable to that of imported valves.

Objective To investigate the independent risk factors for acute severe cholangitis and related protective factors, and to construct a risk prediction scoring model for acute severe cholangitis. Methods A retrospective analysis was performed for the clinical data of 381 patients with acute cholangitis who were admitted to Department of Hepatobiliary Surgery, The 940th Hospital of Joint Logistics Support Force of Chinese People's Liberation Army, from January 2016 to July 2021, among whom there were 273 patients with non-severe cholangitis and 108 patients with severe cholangitis. Univariate and multivariate logistic regression analyses were used to screen out the independent risk factors for acute severe cholangitis and related protective factors, and then a logistic regression model was established. The receiver operating characteristic (ROC) curve was used to evaluate the discriminatory ability of the model, the calibration curve was used to evaluate the prediction accuracy of the model, and decision curve analysis (DCA) was used to evaluate the clinical value of the model. Moreover, the enhanced Bootstrap method was used to perform internal validation of the model and evaluate the performance of the model in internal validation. The model was visualized by the construction of Web calculator, nomogram, and scoring system. The two-independent-samples t test was used for comparison of normally distributed continuous data between groups, and the Mann-Whitney U test was used for comparison of non-normally distributed continuous data between groups; the chi-square test was used for comparison of categorical data between groups. Results The univariate and multivariate logistic regression analyses showed that total bilirubin (TBil) (odds ratio [ OR ]=1.014, 95% confidence interval [ CI ]: 1.009-1.020, P < 0.001), percentage of neutrophils ( OR =1.128, 95% CI : 1.088-1.175, P < 0.001), and age ( OR =1.053, 95% CI : 1.027-1.082, P < 0.001) were independent risk factors, and albumin (Alb) ( OR =0.871, 95% CI : 0.817-0.924, P < 0.001) was a protective factor. The above independent risk factors and protective factor were included in the logistic regression analysis for model fitting, and the predictive model obtained had an area under the ROC curve (AUC) of 0.925 (95% CI : 0.897-0.952), with a specificity of 0.817 and a sensitivity of 0.935 at the optimal cut-off value of 0.245. The calibration curve showed that the predicted probability of the model was approximately equal to the actual probability, with a Brier value of 0.098, and the decision curve analysis showed that the model had a higher net income within the threshold probability interval of 0.1-0.9. Internal validation showed an AUC internal validation of 0.915 and a Brier value internal verification of 0.106. Conclusion TBil, percentage of neutrophils, and age are independent risk factors for acute severe cholangitis, while Alb is a protective factor. The established risk prediction scoring model has good discriminatory ability, calibration, and clinical value and can identify patients with acute severe cholangitis at an early stage, which provides a reference for subsequent diagnosis and treatment.

Objective To design and develop an air purification system for intensive care ambulances,which can effectively purify the air in the compartment and sterilize the microbes in the air.Methods By integrating titanium dioxide photocatalysts with air filtration materials,an air purification system was designed that was capable of effective sterilization of microbes in the air via photocatalytic oxidation and decomposition,and of effective filtration of particles in the air through HEPA filters.The protection effect was evaluated by air filtration and sterilization tests in accordance with the related national standards.Results The air cleanliness could reach the 100 000 level with bacteria counts no more than 1 CFU per pan for 15 minutes in the ambulance compartment when the air purification system worked normally,which could meet the demands of environmental hygienic standards for intensive care units.Conclusion The air purification system can effectively purify and sterilize the air in the compartment of an intensive care ambulance.The effects of air purification meet the requirements of related hygienic standards,which can satisfy the demands of treatment and intensive care for the victims in the ambulance.

To assure the clinical quality and requirement of CT shelter used in field environment, the factors related with the practical application were studied. The evaluation indicators of CT equipment were investigated. Based on the technical modification of vehicle shelter CT, the scanning conditions of shelter CT were analyzed. Moreover, the comparative study was done between shelter CT and common CT in hospitals. In result, in order to meet maneuverability application in the field, vehicle shelter CT was restrictive by the field conditions, traffic impacts and running requirement. The application of vehicle shelter CT was affected by the factors, such as mechanical stabilization, moving precision, power fluctuations and variations of temperature and humidity, etc. The results were helpful to improve the clinical quality of vehicle shelter CT and made a base for the quality control study in the future.
Humidity ; Temperature ; Tomography, X-Ray Computed ; instrumentation

To assure the clinical quality and requirement of CT shelter used in field environment, the factorsrelated with the practical application were studied. The evaluation indicators of CT equipment were investigated. Based on the technical modification of vehicle shelter CT, the scanning conditions of shelter CT were analyzed. Moreover, the comparative study was done between shelter CT and common CT in hospitals. In result, in order to meet maneuverability application in the field, vehicle shelterCT was restrictive by the field conditions, traffic impacts and running requirement. The application of vehicle shelter CT was affected by the factors, such as mechanical stabilization, moving precision, power fluctuations and variations of temperature and humidity, etc. The results were helpful to improve the clinical quality of vehicle shelter CT and made a base for the quality control study inthe future.

Objective To strengthen the scientific management of automatic processor and promote QC, based on analyzing QC management chart for automatic processor by statistical method, evaluating and interpreting the data and trend of the chart. Methods Speed, contrast, minimum density of step wedge of film strip were measured everyday and recorded on the QC chart. Mean ( ), standard deviation ( s ) and range(R) were calculated. The data and the working trend were evaluated and interpreted for management decisions. Results Using relative frequency distribution curve constructed by measured data, we can judge whether it is a symmetric bell shaped curve or not. If not, it indicates a few extremes overstepping control limits possibly are pulling the curve to the left or right. If it is a normal distribution, standard deviation( s ) is observed. When ?2s lies in upper and lower control limits of relative performance indexes, it indicates the processor works in stable status in this period. Conclusion Guided by statistical method, QC work becomes more scientific and quantified. We can deepen understanding and application of the trend chart, and improve the quality management to a new step.