Clinical remission and transmural healing of ustekinumab in patients with Crohn's disease / 北京大学学报(医学版)

Objective:To treat the Crohn's disease(CD)patients with ustekinumab(UST),to eva-luate their clinical and endoscopic remission,and to evaluate their transmural response(TR)and trans-mural healing(TH)condition using intestinal ultrasonography(IUS).Methods:Retrospective analysis was made on patients diagnosed with CD in Peking University People's Hospital from January 2020 to Au-gust 2022,who were treated with UST for remission induction and maintenance therapy.All the patients were evaluated on both week 8 and week 16/20 after treatment,including clinical,biochemical indica-tors,colonoscopy and IUS examination.Results:A total of 13 patients were enrolled in this study,inclu-ding 11 males and 2 females.The minimum age was 23 years,the maximum age was 73 years and the mean age was 36.92 years.All the patients were in the active stage of disease before treatment,and the average Best Crohn's disease activity index(Best CDAI)score was 270.12±105.55.In week 8,the Best CDAI score of the patients decreased from 270.12±105.55 to 133.16±48.66(t=4.977,P＜0.001).Eight patients achieved clinical remission while 5 patients remained in the active stage.Nine patients underwent colonoscopy evaluation.The average simple endoscopic score for Crohn's disease(SES-CD)score decreased from 10.71±7.14 before treatment to 6.00±7.81(t=2.483,P=0.048)in week 16/20.Four patients achieved endoscopic remission while 5 patients did not.In week 8,5 pa-tients achieved TR,2 patients achieved TH,the other 6 patients did not get TR or TH.In week 16/20,6 patients achieved TR,3 patients achieved TH while the other 4 patients did not get TR or TH.There was no significant statistical difference in the TR effect of UST between small intestine and colon lesions(Fisher test,P＞0.999).The rate of UST transmural response in the patients who had had previous bio-logical agent therapy was lower than those with no previous biological agent therapy,but there was no sig-nificant statistical difference(Fisher test,P=0.491).Conclusion:After treatment of UST,the clinical and endoscopic conditions of the CD patients had been improved,and some patients could achieve clini-cal remission and endoscopic remission.UST had good TR and TH effects on CD.TR might appear in week 8,and the TR effect increased in week 16/20.There was no significant statistical difference in the TR effect between small intestine and colon lesions.TR effect of UST was better in the patients who had no previous biological agent therapy than those who had had other biological agents,but the result had no significant statistical difference.

Surgical transmural ablation of atrial fibrillation based on visualization analysis of CiteSpace and VOSviewer / 中国胸心血管外科临床杂志

@#Objective To analyze the current status and hotspots of surgical transmural ablation of atrial fibrillation using CiteSpace and VOSviewer. Methods The Web of Science Core Collection database was used as the data source. The CiteSpace 5.8.R3 and VOSviewer software were used to analyze the related studies on surgical transmural ablation of atrial fibrillation about the authors, countries/institutions, literature co-citation and keywords. Results A total of 109 articles were enrolled. Damiano RJ was the most prolific researcher, while Cox JL was the author with the highest number of citations. The United States was the leading country in this research field. The University of Washington was an important institution in the study of atrial fibrillation transmural ablation. The main hotpots were the effectiveness of surgical ablation, especially Cox-maze procedure, selection of the energy source of surgical ablation, combination of surgical and catheter ablations, and pulmonary vein isolation. Conclusion This study visualizes the current research status of surgical ablation of atrial fibrillation. How to improve the effectiveness and transmurality of surgical ablation is a hot research topic in the surgical treatment of atrial fibrillation. The combination of electrophysiology mapping and surgical ablation may be the development direction in the surgical treatment of atrial fibrillation.

Profile and outcomes of symptomatic pancreatic fluid collections at a tertiary care hospital

Background: Pancreatic fluid collections (PFCs) are seen in about 50% cases of pancreatitis. Most PFCs are usually asymptomatic and resolve spontaneously not requiring intervention. However, symptomatic and complicated PFCs require intervention. In this study we aimed at estimating clinical characteristics, demographics, modalities of treatment and their success rates. Methods: 40 patients with symptomatic PFCs were included in this study. Clinical characteristics, type and location of PFC, indication for treatment, type of intervention, their success and complication rates were recorded. Results: Among 40 patients, 29 were male and 11 females with mean age of 40.2±7.5 years. The most common PFC was pseudocyst (62.5%) followed by walled off necrosis (WON) (25%). The most common indication for intervention was abdominal pain (50%) followed by gastric outlet obstruction (25%), obstructive jaundice (15%) and sepsis (10%). The success rate of EUS guided transmural drainage was 95.6% for pseudocyst and 77.7% for WON. The rate of adverse events was 32% in pseudocysts and 40% in WON. DEN (direct endoscopic necrosectomy) was done in 3 cases of infected WON. Conclusions: The most common PFC seen in practice is pseudocyst followed by WON. Endoscopic (EUS guided) transmural drainage has emerged as the first line intervention for symptomatic PFCs. The rate of complications and associated morbidity is much lesser with endoscopic procedures compared to surgery. The success rate of endoscopic intervention is higher in cases of pseudocyst but complications are higher in necrotic collections.

Efficacy of transgastric combined with percutaneous endoscopy for infected pancreatic necrosis / 中华消化内镜杂志

Objective:To evaluate the efficacy of transgastric combined with percutaneous endoscopic treatment for infected pancreatic necrosis (IPN).Methods:Clinical data of 19 IPN patients who received transgastric combined with percutaneous endoscopy at the Gastroenterology Intensive Care Unit of Nanjing Drum Tower Hospital from August 2015 to August 2020 were retrospectively studied. The clinical efficacy and the procedure-related complications were analyzed.Results:The mean procedure of endoscopic transmural drainage (ETD) was 1.1±0.3 times. During ETD procedure, lumen-apposing metal stents (LAMS) were placed in 9 patients, metal coated stents in 2 patients, double pigtail plastic stents in 7 patients, and only a nasal cyst drainage tube in 1 patient. All 19 patients received 12-14 F drainage catheters for drainage during the first percutaneous catheter drainage (PCD) treatment with the mean number of catheters of 1.8±1.2. Double cannulas was subsequently replaced in 3 of them for continuous drainage, and a percutaneous metal coated stent was replaced in 1 patient. The culture results of drainage fluid were 11 cases of gram-negative bacilli and gram-positive cocci, 4 cases of gram-positive cocci, 1 case of gram-positive bacilli, 3 cases of gram-negative bacilli. Among 19 patients, 4 cases had concurrent fungal infections. The mean number of debridement was 3.1±1.8 times, 2 cases of which were treated with endoscopic transluminal necrosectomy combined with percutaneous endoscopic necrosectomy. The mean procedure per patient was 6.1±2.4 times. Bleeding occurred in 1 case (5.3%) after the operation. But the bleeding was successfully stopped after endoscopic hemostasis. No serious complications such as gastrointestinal fistula, perforation or pancreatic fistula occurred. One patient died due to sepsis, and 18 other patients showed significant absorption of IPN after the treatment. None of the 19 patients were transferred to laparotomy.Conclusion:Transgastric combined with percutaneous endoscopic approach is safe and effective for IPN.

Resección transmural endoscópica de adenoma colónico residual con fibrosis / Endoscopic full-thickness resection of residual colonic adenoma with fibrosis

Resumen La resección transmural endoscópica es una técnica que permite la resección en bloque de lesiones colónicas en pacientes en los cuales han fracasado los métodos endoscópicos convencionales como la resección mucosa endoscópica o la disección submucosa endoscópica. Presentamos el caso de un hombre de 75 años con antecedentes de adenoma de colon con fibrosis debido a dos intentos previos fallidos de resección endoscópica en otra institución. Realizamos con éxito el procedimiento de resección transmural endoscópica evitando así una cirugía.

Abstract Endoscopic full-thickness resection is a technique that allows in block resection of colonic lesions in patients in whom conventional endoscopic methods such as endoscopic mucosal resection or endoscopic submucosal dissection have failed. We present a case of a 75-year-old man with history of a difficult-to-resect colon adenoma. He had undergone two previous failed attempts of endoscopic mucosal resection due to non-lifting sign in another center. We successfully performed an endoscopic full-thickness resection procedure, avoiding unnecessary surgery.

Transmurally migrated gossypiboma rarely posing as surgical site infection: a case report and review of literature

The term gossypiboma is used to describe a retained surgical sponge or gauge after surgery. The clinical features range from being asymptomatic to frank bowel obstruction, perforation and peritonitis. Radiological modalities also do not provide a definite diagnosis. We report a case of a 30-year-old lady who presented to the emergency room with recurrent surgical site infection. She had a history of caesarean section 5 months ago. Following the caesarean section, she developed superficial wound dehiscence which was re-sutured. At the present facility, the lady underwent Computed tomography (CT) scan and was suspected to have a foreign body around the gut. She was planned for an exploratory laparotomy. Upon laparotomy, a large thick-walled ileal loop with some unusual intra luminal mass was found. Dense adhesions were present between the ileal loop and sigmoid colon. Adhesiolysis led to an iatrogenic sigmoid colon perforation, around 2 cm length. On incision over the ileal loop, surgical sponge was retrieved. Ileal loop was resected along with perforated site with end-to-end ileo-ileal anastomosis was done. Primary repair of sigmoid colon perforation was done. Patient was stable in postoperative period. Although rare, gossypiboma should be kept in mind as a differential diagnosis in postoperative cases presenting with recurrent surgical site infection.

Effects of hypothermia on the repolarization duration of ventricular myocytes in rats and its mechanism / 中国应用生理学杂志

To observe the effects of hypothermia on the repolarization duration and the expression of Kir2.1 protein of ventricular myocytes in isolated rat heart and explore the role of Kir2.1 protein. Eighteen healthy adult male Sprague-Dawley rats were randomly divided into three groups (n=6 per group): Control group (C group), 35℃ group (H group), 32℃ group (H group). Langendorff isolated heart models were established. After 15 min 37℃ K-H fluid banlanced perfusion, C group continued to perfuse the K-H solution at 37℃ for 30 minutes, H group continued to perfuse the K-H solution at 35℃ for 30 minutes, H group continued to perfuse the K-H solution at 32℃ for 30 minutes. At 15 min of balanced perfusion (T), and 30 min of continuous perfusion (T), the heart rate,and the MAP in the three layers of the left ventricular anterior wall were recorded, the action potential duration at 50% repolarization (MAPD), the action potential duration at 90% repolarization (MAPD) and transmural dispersion of repolarization(TDR) were calculated. At the same time, the occurrence of arrhythmia was recorded. The expression of Kir2.1 protein was measured by Western blot. The average optical density (AOD) and the distribution of Kir2.1 protein were measured by immunohistochemistry in the ventricular tissue measured by electrophysiology. Compared with T, the heart rate was decreased, MAPD and MAPD were prolonged significantly (P＜0.05), and TDR was increased significantly (P＜0.05) in H group, H group at T. Compared with C group, the HR was decreased, the MAPD was prolonged significantly (P＜0.05), TDR was increased significantly (P＜0.05),the expression and the AOD of Kir2.1 protein were decreased significantly (P＜0.05) in Hgroup, Hgroup at T. Compared with H group, the heart rate of H group was decreased significantly (P＜0.05), MAPD and MAPD were prolonged significantly (P＜0.05), and TDR was increased significantly (P＜0.05) at T. The distribution of Kir2.1 protein in group C was normal, while the distribution of Kir2.1 in H group and H group was disordered. Hypothermia prolonged the ventricular duration of repolarization and increased the dispersion of repolarization. The mechanism is related to the down-regulation the expression of Kir2.1 protein and the disorder of the distribution of Kir2.1 protein.

Endoscopic Management of Large Peripancreatic Fluid Collections in Two Pediatric Patients by Endoscopic Ultrasound-guided Transmural Drainage / 대한소아소화기영양학회지

Interacciones cardiopulmonares: de la fisiología a la clínica / Cardiopulmonary Interactions: from Physiology to Clinic

Resumen: Las Interacciones Cardiopulmonares (ICP) corresponden al conjunto de interrelaciones entre el sis tema respiratorio y el cardiovascular, durante el ciclo respiratorio y cardíaco. Estas interacciones varían dependiendo de si el paciente se encuentra en ventilación espontánea o mecánica, afectando en distintos grados la precarga y postcarga, tanto del ventrículo derecho e izquierdo. El entender estas interacciones, resulta esencial al momento de manejar pacientes críticamente enfermos, en donde las manipulaciones de la precarga y postcarga, son de especial importancia al momento de optimizar el débito cardíaco y la entrega de oxígeno a los tejidos. En este artículo se presentan los principios fisiológicos que permiten entender las interacciones cardiopulmonares en ventilación espontánea y en ventilación mecánica, aplicadas a situaciones clínicas específicas, lo que nos ayudará a utilizarlas como herramientas en el manejo de los pacientes.

Abstract: Cardiopulmonary Interactions (CPI) refer to the interplay between the respiratory and cardiovascu lar systems during the respiratory and cardiac cycle. These interactions vary depending on whether the patient is in spontaneous or mechanical ventilation and affect the preload and afterload of both ventricles at different levels. Understanding CPI is essential to the management of critically ill pa tients, where preload and afterload manipulations are specialy important to optimize cardiac output and oxygen delivery to the periphery. The present article reviews the physiological principles required to understand CPI in patients both in spontaneous and mechanical ventilation using specific clinical scenarios to facilitate its use as part of day to day clinical practice.

Investigations on effect of taurine-magnesium coordination compound against SQT2 in isolated hearts of guinea pig / 中国药理学通报

Aim To investigate the effect of taurine-magnesium coordination compound (TMCC) on elec-trocardiogram of isolated guinea pig hearts, hoping to describe a primary research on its characteristic of anti-short QT syndrome. Methods The isolated guinea pig heart was retrograde perfused using Langendorff tech-nique. In order to determine the effects of TMCC on QT interval, transmural dispersion of repolarization, effective refractory period, instability of RR interval and instability of QT interval in the presence of potassi-um channel opener pinacidil, the electrocardiogram of isolated guinea pig hearts was recorded using Biopac physiological recorder. Results The shortened QT in-terval and the effective refractory period induced by pinacidil could be prolonged by TMCC; the increased transmural dispersion of repolarization induced by pinacidil could be decreased by TMCC; the increased instability of RR and QT interval induced by pinacidil could be decreased by TMCC. Conclusion TMCC has the effects of anti-SQT2 by prolonging the QT inter-val and the effective refractory period, reducing the transmural dispersion of repolarization and instability.

Anti-arrhythmic effects of taurine-magnesium coordination compound on torsades de pointes / 中国应用生理学杂志

OBJECTIVES@#To investigate the effect of taurine magnesium coordination compound (TMCC) on torsades de pointes (TdP) in isolated guinea pig hearts.@*METHODS@#Healthy male guinea pigs weighting 250~300 g were randomly divided into 4 groups:①TdP model group (=7):Isolated hearts were perfused by normal K-H solution 20 minutes, then perfused by slowly activated delayed rectifier potassium current(IKs) blocker 10mol/L Chromanol 293B under hypokalemic solution(1.8 mmol/L) to establish TdP model;②~④ TdP model + TMCC group (=6):Isolated hearts were perfused by normal K-H solution for 20 minutes, then perfused by IKs blocker 10mol/L Chromanol 293B under hypokalemic solution(1.8 mmol/L) for 60 minutes, at the same time TMCC which concentration was 1, 2, 4 mmol/L was administered respectively by Langendorff retrograde aortic perfusion method. Cardiac surface electrocardiogram of guinea pigs was collected and recorded by Biopac electrophysiological recorder. Incidence of TdP, transmural dispersion of repolarization (TDR), instability of QT interval were acquired from Lead Ⅱ electrocardiograph (ECG) wave forms to describe the effect of TMCC on TdP model. Datas were acquired at the time of 20 min and pre-TdP, in case there was no TdP observed, a value of 60 min was entered for calculation purpose.@*RESULTS@#Incidence of TdP in TdP model group was 6/7. TdP incidence could be decreased significantly by 1, 2, 4 mmol/L TMCC, and was 5/6, 1/6, 0/6 respectively. Compared with the pre-drug, Chromanol 293B under hypokalemic solution in TdP model group increased TDR(corrected) evidently(0.05). Compared with the TdP model group, 2, 4 mmol/L TMCC could evidently decrease the instability of QT interval induced by Chromanol 293B under hypokalemic solution(<0.05). During the establishment of TdP model, P waves in more than one cardiac cycle continuously were disappeared in ECG. However, P wave could always be seen independent in ECG acquired from TdP model + TMCC group.@*CONCLUSIONS@#TMCC can play the role against TdP through decreasing TDR and instability of QT interval, and inhibiting early after depolarization(EAD).

T wave

The T wave in a surface electrocardiogram (ECG) indicates the diastolic phase in the cardiac cycle. Even though the cellular basis of T-wave morphology in surface ECG remains unclear in clinical cardiology, the morphology may be determined by the transmural voltage gradient during the repolarization period that underlies the changes in the T wave and QT interval. The heterogeneous distribution of electrophysiological activity across the heart is essential for normal cardiac function. However, excessive heterogeneity may contribute to arrhythmogenesis and sudden cardiac death. This paper will provide an overview of T wave genesis and the contribution to action potential duration (APD), in which ion channels are involved in the repolarization period, with special emphasis on K+ channels involved in phase 3 repolarization. These channels are primarily Kv11.1 (hERG1), Kv7.1 (KCNQ1), and Kir2.1 (KCNJ2), which are the α-subunits responsible for conducting I(Kr), I(Ks), and I(K1). Changes in the T wave and QT interval that are affected by both functional loss and gain of these currents are associated with various arrhythmogenic diseases. This review also briefly discusses arrhythmogenesis in diseases that are manifested by changes in the T wave and QT interval.

Role of gap junction Cx43 in dexmedetomidine for prevention of reperfusion induced arrhythmias during ischemia-reperfusion in isolated rabbit hearts / 临床麻醉学杂志

Objective To investigate the effect of dexmedetomidine on myocardial repolarization heterogeneity and the expression of Cx43 during ischemia-reperfusion and the role of Cx43 in the dexmedetomidine for inhibition of myocardial repolarization heterogeneity during ischemia-reperfusion in isolated rabbit hearts.Methods Eighteen healthy adult rabbits,weighing (2.0±0.5) kg,were randomly divided into three groups after Langendorff isolated heart perfusion model had been prepared and K-H fluid had been perfused and balanced 15 min.In the control group (group C),37℃ K-H fluid was continuously perfused and balanced for 150 min.In group IR,K-H fluid was stopped after perfusion continue filling for 15 min,and then made the cardiac stop for 60 min with the injection of Thomas solution 10 ml/kg while the heart was protected by the 4℃ Thomas solution around.Following the reperfusion of 4℃ Thomas solution 5 ml/kg was performed for 30 min and the heart was resuscitated by the perfusion of K-H fluid for 60 min.In dexmedetomidine group given (group DEX),dexmedetomidine was added in the K-H fluid and the Thomas solution 25 ng/ml.The other procedures were the same as those of group IR.The heart rate (HR),90% monophasic action potential duration (MAPD90) were recorded at the time of balance perfusion record 15 min (T0),continue perfusion 15 min/balance 30 min (T1),reperfusion 30 min/balance 120 min (T2) and reperfusion 60min/balance 150 min (T3).The transmural dispersion of repolarization (TDR) was calculated.To observe the cardiac reperfusion arrhythmia and rebeating time and recording.Detection expression of Cx43 in the left ventricular myocardial by Western blot and immunohistochemistry at T3.Results Group DEX cardiac resuscitation time was significantly shorter than that of group IR (P<0.05).In group DEX.Compared with T0,HR was significantly decreased and TDR was significantly increased in groups IR and DEX at T2、T3 (P<0.05).Compared with group IR,the TDR of group DEX was significantly decreased at T2、T3 (P<0.05).Compared with group C,the expression of Cx43 was decreased (P<0.05) and the distribution was not uniform in groups IR and DEX.Compared with group IR,the expression of Cx43 was decreased (P<0.05) and the distribution was improved in group DEX.Conclusion Dexmedetomidine could inhibits myocardial repolarization heterogeneity of ischemia-reperfusion injury,and thus play a stable cardiac conduction,reduce reperfusion arrhythmias,and its mechanism may be that dexmedetomidine could inhibits gap junctional uncoupling and inhibits expression and distribution of connexins decreased.

Effect of mallotoxin against LQT2 induced by E-4031 in isolated guinea pig hearts and cardiomyocytes / 中国药理学通报

Aim To investigate the effect of mallotoxin (MTX) on LQT2 induced by E-4031 in isolated guinea pig hearts and ventricular myocytes.Methods The isolated guinea pig heart underwent retrograde perfusion using Langendorff technique.In order to determine the effects of different concentrations of MTX on QT/QTc interval,transmural dispersion of repolarization (TDR) and index of cardiac electrophysiological balance (iCEB) in the absence and presence of hERG channel blocker E-4031,the electrocardiogram of isolated guinea pig hearts was recorded using Biopac physiological record.Single ventricular myocytes were isolated from guinea pig heart by enzymatic dissociation.Effects of MTX on action potential duration (APD) in the absence and presence of E-4031 were recorded by current clamp mode using whole patch clamp technique.Results MTX shortened the QT interval,reduced TDR,and decreased iCEB in isolated guinea pig heart.MTX could reverse the prolongation of QT interval and the increased TDR induced by E4031.MTX shortened the action potential duration and decreased APDgo,APD60 and APD30 in isolated guinea pig ventricular myocytes.MTX could reverse the prolongation of action potential repolarization duration induced by E-4031.Conclusion MTX shortens QT interval,decreases TDR,reduces iCEB,as well as shortens APD,thus reversing LQT2 induced by E4031.

Assessment of left ventricular systolic function in hypertrophic cardiomyopathy patients with normal left ventricular ejection fraction by using echocardiography layer strain / 中华医学超声杂志（电子版）

Objective To investigate the value of quantitative analysis of the left ventricular longitudinal strain in patients with hypertrophic cardiomyopathy (HCM) and with normal left ventricular ejection fraction (LVEF) by using two-dimensional speckle tracking imaging.Methods Twenty-eight HCM patients with normal LVEF (all of the cases were non obstructive HCM),who were diagnosed by clinical and ultrasound echocardiography between January 1,2015 and January 1,2016 in the First Affiliated Hospital of Dalian Medical University,served as the experimental group.And twenty healthy volunteers served as the healthy control group.The peak longitudinal strain (LPS) of the left ventricle and the systolic peak of the left ventricle were calculated by the STE technique.The indexes such as the transmural gradient (△ LS=LPSEndo-LPSEpi)and the transmural gradient percentage (△ LS％=△ LS/LPSEndo) were calculated.The Peak systolic longitudinal strain of endocardium (LPSEndo),the peak systolic longitudinal strain of mid-cardium (LPSMid),the peak systolic longitudinal strain of epicardium (LPSEpi),the peak systolic longitudinal strain of basal segment (LPSb),the peak systolic longitudinal strain of middle segment (LPSm),the peak systolic longitudinal strain of apical segment (LPSa),the global peak systolic longitudinal strain (GLPS) and other left ventricular myocardial strain,such as △ LS,△ LS％,in both the HCM group and the healthy control group,were analyzed by using independent samples t test comparison.For each layer of the left ventricle and the overall myocardial longitudinal strain,two independent sample t test was used for comparison between groups,and LSD-t test was used for intra-group comparison.Results (1) There was a gradient of LPS among the three layers and the three segments in both of the two groups:LPSEndo and LPSMid [(18.36±4.97)％ vs (13.80±4.23)％,(26.41±2.93)％ vs (22.19±2.49)％],the difference was statistically significant (t=5.550,8.529,P ＜ 0.05);LPSEndo and LPSEpi [(18.36±4.97) ％ vs (11.91 ±3.63)％,(26.41±2.93)％ vs (19.43±2.20)％],the difference was statistically significant (t=5.550,8.529,P ＜ 0.05);There was significant difference between LPSMid and LPSEpi in the healthy control group [(22.19 ± 2.49)％ vs (19.43 ± 2.20)％,t=3.709,P ＜ 0.05)],that was,LPSEndo ＞ LPSMid ＞ LPSEpi.LPSa and LPSm,the difference was statistically significant (t=4.029,6.839,P ＜ 0.05);LPSa and LPSb,the difference was statistically significant (t=5.304,9.887,P ＜ 0.05);There was significant difference between LPSm and LPSb in the healthy control group (t=4.170,P ＜ 0.05);that was,LPSa ＞ LPSm ＞ LPSb.In the HCM group,LPS in the 3 layers,3 segments,and the whole left ventricular wall were lower than that of the the healthy control group,the differences were statistically significant [GLPS:(14.63± 3.75)％ vs (22.68±2.51)％,t=-8.347;LPSEndo to LPSEpi:t=-6.477,-7.909,-8.242;LPSa to LPSb:t=-6.647,-8.790,-7.267;all P ＜ 0.05).(2) Compared with the healthy control group,both the segmental gradient and global transmural gradient in the HCM group were found reduced,but the difference had no statistical significance (all P ＞ 0.05).(3) The transmural gradient percentage both in the healthy control group and the HCM group were reduced from the apical segment to the basal segment,the difference were statistically significant (HCM group:t=9.985,5.969;healthy control group:t=17.513,7.043;all P ＜ 0.05).Compared with the healthy control group,the △ LS％a and the △ LS％m of HCM group were significantly higher [(58.86± 11.32)％ vs (43.70±4.73)％,(28.43± 11.48)％ vs (20.30± 3.66)％],and the difference was statistically significant (t=5.634,3.049,all P ＜ 0.05).Conclusions (1) Using 2D-STI could accurately determine the regional or the global left ventricular systolic function in patients with HCM.(2) The transmural gradient percentage can be more sensitive to reflect the change of the transmural gradient,and more research needed to explore its value for clinical application.

Endoscopic Ultrasound-Guided Pancreatobiliary Endoscopy in Surgically Altered Anatomy

Endoscopic retrograde cholangiopancreatography (ERCP) has become the mainstay of therapy for pancreatobiliary diseases. While ERCP is safe and highly effective in the general population, the procedure remains challenging or impossible in patients with surgically altered anatomy (SAA). Endoscopic ultrasound (EUS) allows transmural access to the bile or pancreatic duct (PD) prior to ductal drainage using ERCP-based techniques. Also known as endosonography-guided cholangiopancreatography (ESCP), the procedure provides multiple advantages over overtube-assisted enteroscopy ERCP or percutaneous or surgical approaches. However, the procedure should only be performed by endoscopists experienced in both EUS and ERCP and with the proper tools. In this review, various EUS-guided diagnostic and therapeutic drainage techniques in patients with SAA are examined. Detailed step-by-step procedural descriptions, technical tips, feasibility, and safety data are also discussed.

Effects of dexmedetomidine on the monophasic action potential duration and transmural dispersion of re-polarization during ischemia-reperfusion in isolated rabbit hearts / 临床麻醉学杂志

Objective To study the effects of dexmedetomidine on the monophasic action po-tential duration and the transmural dispersion of repolarization during ischemia-reperfusion of isolated rabbit hearts and thus explore its effect on myocardial ischemia-reperfusion electrophysiological char-acteristics.Methods Eighteen healthy adult rabbits,weighing (2.0±0.5)kg,were randomly divided into 3 groups after successful preparation of Langendorff isolated heart perfusion model and 1 5 min perfusion and balance of K-H fluid.In the control group (group C),37 ℃ K-H fluid was continuously perfused and balanced for 1 50 min.In the ischemia/reperfusion group (group IR),K-H fluid was stopped after continuous perfusion and balance for 1 5 min and cardiac arrest was induced for 60 min with the injection of Thomas solution (4 ℃,10 ml/kg)while the heart was protected by the low tem-perature Thomas solution (4 ℃)around it.Reperfusion of Thomas solution (4 ℃,5 ml/kg)was performed for 30 min and the heart was resuscitated by the perfusion of K-H fluid for 60 min.In dexmedetomidine group (group DEX),dexmedetomidine (25 ng/ml)was added in the K-H fluid and the Thomas solution.Other procedures were same as in group IR.Heart rate(HR),monophasic ac-tion potential amplitude (MAPA)of the three layers of heart [endocardium (Endo),myocardium (Mid)and epicardium (Epi)],0 phase maximal increase rate (Vmax),90% monophasic action po-tential duration (MAPD90 )and transmural dispersion of repolarization (TDR)were recorded at the time of continuous balance perfusion 1 5 min(T0 ),continuous perfusion 1 5 min/balance 30 min(T1 ), reperfusion 30 min/balance 120 min(T2 )and reperfusion 60 min/balance 1 50 min(T3 ).Cardiac ar-rhythmia and resuscitation time at cardiac reperfusion were observed,without using drugs to restore normal cardiac rhythm.Results In group DEX,cardiac resuscitation time was significantly shorter (1 6.67±3.78)s than that in group IR (46.33±7.29)s (P <0.05);At T2 ,in group IR,arrhythmia was seen in 6 rabbits and normal cardiac rhythm was restored within 2 min in two rabbits,while in group DEX,arrhythmia was seen in 2 rabbits and normal cardiac rhythm was restored within 2 min in one rabbit,without the use of any drugs.When compared with T0 ,HR was slower at T2 and T3 in group IR and at T1-T3 in group DEX (P <0.05);Compared with T1 ,HR was slower at T2 and T3 in group DEX (P <0.05);Compared with T2 and group C,HR was slower at T3 in group DEX;At T1-T3 ,HR in group DEX were significantly slower than that in group IR (P <0.05).Compared with T0 ,MAPD90 of Mid at T1 and Epi,Mid,Endo at T2 and T3 in group DEX were significantly extend-ed (P <0.05);Compared with T1 ,MAPD90 of Epi,Mid,Endo in group DEX were significantly ex-tended at T3 ;MAPD90 of Mid in group DEX was significantly longer than that in group C at T3 (P <0.05);At T2 and T3 ,MAPD90 of Epi,Mid,Endo in group DEX were longer than that in group IR (P <0.05).Compared with T0 and group C,TDR at T2 and T3 in group IR and at T1-T3 in group DEX significantly increased (P <0.05),while TDR in group DEX were less than that in group IR at T2 and T3 (P <0.05).Conclusion Dexmedetomidine appeared to prolong MAPD and restrain the dis-proportion of resuscitation of myocardial ischemia-reperfusion injury.Dexmedetomidine could have the effect of stabilizing myocardial ischemia-reperfusion electrophysiological characteristics.

Evaluation of left ventricular transmural mechanics after anthracycline chemotherapy in patients with breast cancer by speckle tracking imaging / 中华超声影像学杂志

Objective To evaluate the left ventricular transmural mechanics changes of breast cancer patients between before and after anthracycline chemotherapy by two-dimensional speckle tracking imaging (2D-STI),and to predict early cardiotoxicity caused by anthracycline.Methods Forty-six breast cancer patients with postoperative anthracycline-based chemotherapy were recruited.Echocardiography were performed on all subjects before and at 1 ,3 and 6 anthracycline-based chemotherapeutic cycle.Global longitudinal strain(GLS),endocardial longitudinal strain(LS-endo),epicardial longitudinal strain(LS-epi), global radial strain (GRS),endocardial radial strain (RS-endo ),epicardial radial strain (RS-epi ),global circumferential strain (GCS),endocardial circumferential strain (CS-endo)and epicardial circumferential strain(CS-epi) were assessed by 2D-STI and transmural myocardial strain gradient-longitudinal strain (TMSG-LS),transmural myocardial strain gradient-radial strain(TMSG-RS),transmural myocardial strain gradient-circumferential strain(TMSG-CS)were calculated.Conventional echocardiographic parameters and strain-related parameters before and after chemotherapy were compared. The receiver operating characteristics(ROC)curve was performed to determine sensitivity and specifity of strain parameters for prediction value of cardiotoxicity induced by anthracycline chemotherapy.Results ①After the sixth cycle of anthracycline chemotherapy,9 patients (16.4%)had developed anthracycline-induced cardiotoxicity,and 37 patients (80.4%)did not meet the criteria for cardiotoxicity.② There were no significant differences in conventional echocardiography parameters between before and after chemotherapy (P > 0.05 ).Left ventricular ejection fraction (LVEF),fractional shortening (FS)and E/A significantly decreased,but E/e significantly increased after six cycles of chemotherapy (P LS-endo> GLS> LS-epi.Conclusions After three cycles of chemotherapy,the decreases of TMSG-LS,LS-endo,GLS and LS-epi preceded the change of LVEF and other strain parameters,TMSG-LS and LS-endo can accurately and early detect anthracycline chemotherapy-induced cardiotoxicity.

Effects of remifentanil on monophasic action potential and transmural dispersion of repolarization in rabbit myocardium / 中国病理生理杂志

AIM:To study the effect of remifentanil on monophasic action potential and transmural dispersion of repolarization (TDR) in the 3-layer myocardium of isolated rabbit hearts .METHODS:Adult rabbits (n=18, 2.0 ~2.5 kg) were used to isolate the hearts for preparing Langendorff perfusion model .The hearts were randomly divided into 3 groups after perfusion with K-H solution for 15 min: the perfusion in control group ( C group ) continued for 60 min; the hearts in remifentanil group ( R group ) were perfused with 12 μg/L remifentanil K-H solution for 60 min; the hearts in remifentanil+aminophylline group ( RA group ) were given 60-min perfusion of 12 μg/L K-H remifentanil +30 mg/L aminophylline .The HR and 3 layers of myocardial monophasic action potential ( MAP) in the left ventricular anterior wall were recorded at time points after balanced infusion for 15 min ( T0 ) , and continued perfusion for 15 min ( T1 ) , 30 min ( T2 ) and 60 min ( T3 ) .The monophasic action potential duration of repolarization at 90%( MAPD90 ) and the transmural dispersion of repolarization (TDR) were calculated.The early afterdepolarization, delay afterdepolarization and arrhythmia were also observed.RESULTS:In R group, slower HR and prolonger MAPD90 and TDR at T1 ~T3 were observed as com-pared with those at T0(P<0.05).R group showed slower HR and longer MAPD 90 and TDR than C group and RA group (P<0.05).CONCLUSION:Remifentanil slows the HR, extends the MAPD90 and increases the TDR, thus being prone to induce reentry.Aminophylline makes HR faster and MAPD90 shorter, thereby reducing the TDR.

Cellular electrophysiologic mechanisms of tachyarrhythmia in rabbits induced by positive acceleration / 军事医学

Objective To investigate the effect of positive acceleration (+Gz) on monophasic action potential duration of 90%repolarization( MAPD90 ) and transmural dispersion of repolarization ( TDR) in ventricles of rabbits and to explore the cellular electrophysiologic mechanism of tachyarrhythmia induced by positive acceleration .Methods Twenty-four healthy, male New Zealand white rabbits were randomly and equally divided into control group and +Gz group.The +Gz group rabbits were given +8 Gz exposure, 1 min a time, 3 times a day,and a total of 7 days.The two groups were subjec-ted to Holter monitoring at the same time to observe the incidence of tachyarrhythmia .Using the monophasic action potential ( MAP) recording technology , the MAP of the left ventricle was recorded while MAPD 90 and TDR were measured .By using Burst stimulation method , the right ventricular anterior wall of the rabbits was stimulated , and the incidence of tachya-rrhythmia was observed .Results The Holter record showed that the incidence of tachyarrhythmias in +Gz group was 55%(6/11), but the control group did not have any case of tachyarrhythmias .Compared with the control group ,MAPD90 of en-docardial and epicardial cells was significantly decreased in the +Gz group, while MAPD90 of middle myocardial cells did not change significantly ,but TDR was increased obviously .Four rabbits in +Gz group suffered from tachyarrhythmias dur-ing Burst stimulation ,and the incidence of tachyarrhythmias was 40% ( 4/10 ) .Conclusion +Gz exposure can increase the incidence of tachyarrhythmias .The shortened MAPD90 of ventricular muscle cells and the increased TDR may be the cell electrophysiological mechanisms of tachyarrhythmias induced by +Gz.