BACKGROUND Ventricular arrhythmia is a common type of arrhythmia observed in clinical practice.It is primarily characterized by premature ventricular contractions,ventricular tachycardia,and ventricular fibrillation.A...BACKGROUND Ventricular arrhythmia is a common type of arrhythmia observed in clinical practice.It is primarily characterized by premature ventricular contractions,ventricular tachycardia,and ventricular fibrillation.Abnormal formation or transmission of cardiac electrical impulses in patients affects cardiac ejection function.It may present with symptoms such as palpitations,dyspnea,chest discomfort,and reduced exercise tolerance.In severe cases,ventricular arrhy-thmia can even lead to death.Therefore,prompt treatment is very much essential upon diagnosis.The symptoms did not improve after previous conventional drugs and electrical defibrillation treatment,but the ventricular arrhythmia was prevented after the addition of nicorandil.CASE SUMMARY A 75-year-old female patient was admitted to the hospital because of intermittent chest tightness,shortness of breath for 10 days,and fainting once for 7 days.Combined with laboratory tests and auxiliary examination,the patient was tentatively diagnosed with coronary heart disease or arrhythmia-atrial fibrillation.After admission,the patient had intermittent ventricular arrhythmia,which was uncontrolled with lidocaine,defibrillation,and amiodarone.However,when she was treated with nicorandil,the ventricular arrhythmia stopped.Nicorandil mitigates the action potential duration by facilitating the opening of potassium ion channels,thereby regulating the likelihood of premature and delayed depolar-ization in two distinct phases and subsequently averting the onset of malignant ventricular arrhythmia.Nicorandil may inhibit ventricular arrhythmia by dilating coronary arteries,improving coronary microcirculation and reducing myocardial fibrosis.CONCLUSION option for inhibiting ventricular arrhythmias.展开更多
The properties of the inward-rectifying potassium current (IK1) were studied in the single myocytes isolated from adult mouse ventricles by the whole-cell patch-damp technique for the first time. Most of the propertie...The properties of the inward-rectifying potassium current (IK1) were studied in the single myocytes isolated from adult mouse ventricles by the whole-cell patch-damp technique for the first time. Most of the properties of IK1 including channel conductances, activation, inactivation, rectification and external K+ sensitivity in mouse ventricular myocyte were similar to those in other species, but the current-voltage (1-V) curve of mouse ventricular myocyte showed no negative slope, i.e the slope in the range of membrane potential 50 mV positive to the reversal potential (VRev) was virtually flat and remained at a low current level ((59±39) pA). Under the superfusion of Tyrode's solution with 3mmol/L K+ and 3mmol/L Cs+, IK1 in the above region nearly decreased to zero, and then the early after-depolarization (EAD) occurred. The results suggest that this distinctive characteristic of IK1 in mouse ventricular myocyte may relate to the high susceptibility to EA0 in mouse myocardium. The inhibition of IK1 seems to be a prerequisite for the occurrence of EAD in this experiment.展开更多
Normothermic machine perfusion(NMP)is an innovative technique used in solid organ transplantation that involves perfusing the organ with specialized solution or leukocyte depleted red blood cells at near-normal body t...Normothermic machine perfusion(NMP)is an innovative technique used in solid organ transplantation that involves perfusing the organ with specialized solution or leukocyte depleted red blood cells at near-normal body temperature aiming at mimicking physiological conditions,and providing optimal conditions for organ preservation which leads to reduced risk of ischemia reperfusion injury(IRI)when compared to the standard static cold storage(SCS)(1).One of the key advantages of NMP is its ability to assess the quality of the organ in real-time and assessment of the organ performance prior to transplantation.By continuously monitoring parameters such as blood flow,oxygen consumption,and lactate production,clinicians can evaluate the viability of the organ and make more informed decisions about its suitability for transplantation.This real-time assessment can help reduce the risk of transplanting organs that may not function optimally or have a higher likelihood of complications post-transplant.Additionally,NMP may expand the pool of donor organs by allowing for the use of organs that may have been deemed marginal or unsuitable for transplantation using traditional methods(1,2).展开更多
Background:Early allograft dysfunction(EAD)is associated with decreased graft and patient survival rates.This study aimed to identify the severity of EAD and develop a predictive model for EAD after donation after cir...Background:Early allograft dysfunction(EAD)is associated with decreased graft and patient survival rates.This study aimed to identify the severity of EAD and develop a predictive model for EAD after donation after circulatory death(DCD)liver transplantation(LT).Furthermore,the influence of operative time on EAD incidence was also evaluated.Methods:In this retrospective,multicentre cohort study,nomograms were established based on a single-centre training cohort(n=321)and validated in a 3-center validation cohort(n=501).Results:The incidence rate of EAD was 46.4%(149/321)in the training cohort and 40.5%(203/501)in the validation cohort.Of the 149 EAD patients in the training cohort,77 patients with either elevated alanine aminotransferase(ALT)or aspartate aminotransferase(AST)were classified as having EAD type A,and the rest of the EAD patients were classified as having EAD type B.Recipients with EAD type B had lower graft and patient survival rates than recipients with EAD type A(P=0.043 and 0.044,respectively).We further developed a nomogram to predict EAD(graft weight,cold ischemia time,donor age,model for end-stage liver disease(MELD)score)and another nomogram to predict EAD type B(graft weight,cold ischemia time,MELD score).The nomograms for the prediction of EAD and EAD type B had good discrimination[concordance index(C-index)=0.712(0.666-0.758),0.707(0.641-0.773)]and calibration[Hosmer-Lemeshow(HL)P=0.384,P=0.425]in the validation cohort.An increased operative time(>6 h)was associated with increased EAD and EAD type B incidence in the high-risk group(P=0.005,P=0.020,respectively).Conclusions:EAD type B was associated with decreased graft and patient survival rates.The novel nomograms effectively predicted the incidence of EAD and EAD type B in DCD LT patients.展开更多
文摘BACKGROUND Ventricular arrhythmia is a common type of arrhythmia observed in clinical practice.It is primarily characterized by premature ventricular contractions,ventricular tachycardia,and ventricular fibrillation.Abnormal formation or transmission of cardiac electrical impulses in patients affects cardiac ejection function.It may present with symptoms such as palpitations,dyspnea,chest discomfort,and reduced exercise tolerance.In severe cases,ventricular arrhy-thmia can even lead to death.Therefore,prompt treatment is very much essential upon diagnosis.The symptoms did not improve after previous conventional drugs and electrical defibrillation treatment,but the ventricular arrhythmia was prevented after the addition of nicorandil.CASE SUMMARY A 75-year-old female patient was admitted to the hospital because of intermittent chest tightness,shortness of breath for 10 days,and fainting once for 7 days.Combined with laboratory tests and auxiliary examination,the patient was tentatively diagnosed with coronary heart disease or arrhythmia-atrial fibrillation.After admission,the patient had intermittent ventricular arrhythmia,which was uncontrolled with lidocaine,defibrillation,and amiodarone.However,when she was treated with nicorandil,the ventricular arrhythmia stopped.Nicorandil mitigates the action potential duration by facilitating the opening of potassium ion channels,thereby regulating the likelihood of premature and delayed depolar-ization in two distinct phases and subsequently averting the onset of malignant ventricular arrhythmia.Nicorandil may inhibit ventricular arrhythmia by dilating coronary arteries,improving coronary microcirculation and reducing myocardial fibrosis.CONCLUSION option for inhibiting ventricular arrhythmias.
文摘The properties of the inward-rectifying potassium current (IK1) were studied in the single myocytes isolated from adult mouse ventricles by the whole-cell patch-damp technique for the first time. Most of the properties of IK1 including channel conductances, activation, inactivation, rectification and external K+ sensitivity in mouse ventricular myocyte were similar to those in other species, but the current-voltage (1-V) curve of mouse ventricular myocyte showed no negative slope, i.e the slope in the range of membrane potential 50 mV positive to the reversal potential (VRev) was virtually flat and remained at a low current level ((59±39) pA). Under the superfusion of Tyrode's solution with 3mmol/L K+ and 3mmol/L Cs+, IK1 in the above region nearly decreased to zero, and then the early after-depolarization (EAD) occurred. The results suggest that this distinctive characteristic of IK1 in mouse ventricular myocyte may relate to the high susceptibility to EA0 in mouse myocardium. The inhibition of IK1 seems to be a prerequisite for the occurrence of EAD in this experiment.
文摘Normothermic machine perfusion(NMP)is an innovative technique used in solid organ transplantation that involves perfusing the organ with specialized solution or leukocyte depleted red blood cells at near-normal body temperature aiming at mimicking physiological conditions,and providing optimal conditions for organ preservation which leads to reduced risk of ischemia reperfusion injury(IRI)when compared to the standard static cold storage(SCS)(1).One of the key advantages of NMP is its ability to assess the quality of the organ in real-time and assessment of the organ performance prior to transplantation.By continuously monitoring parameters such as blood flow,oxygen consumption,and lactate production,clinicians can evaluate the viability of the organ and make more informed decisions about its suitability for transplantation.This real-time assessment can help reduce the risk of transplanting organs that may not function optimally or have a higher likelihood of complications post-transplant.Additionally,NMP may expand the pool of donor organs by allowing for the use of organs that may have been deemed marginal or unsuitable for transplantation using traditional methods(1,2).
基金supported by grants from the National Science and Technology Major Project(Grant number:2017ZX10203205)National Natural Science Funds for Distinguished Young Scholar of China(Grant number:81625003)+1 种基金Zhejiang Provincial Natural Science Foundation of China(Grant No.LQ17H160006)National Natural Science Foundation of China(Grant number.81570589,81800578).
文摘Background:Early allograft dysfunction(EAD)is associated with decreased graft and patient survival rates.This study aimed to identify the severity of EAD and develop a predictive model for EAD after donation after circulatory death(DCD)liver transplantation(LT).Furthermore,the influence of operative time on EAD incidence was also evaluated.Methods:In this retrospective,multicentre cohort study,nomograms were established based on a single-centre training cohort(n=321)and validated in a 3-center validation cohort(n=501).Results:The incidence rate of EAD was 46.4%(149/321)in the training cohort and 40.5%(203/501)in the validation cohort.Of the 149 EAD patients in the training cohort,77 patients with either elevated alanine aminotransferase(ALT)or aspartate aminotransferase(AST)were classified as having EAD type A,and the rest of the EAD patients were classified as having EAD type B.Recipients with EAD type B had lower graft and patient survival rates than recipients with EAD type A(P=0.043 and 0.044,respectively).We further developed a nomogram to predict EAD(graft weight,cold ischemia time,donor age,model for end-stage liver disease(MELD)score)and another nomogram to predict EAD type B(graft weight,cold ischemia time,MELD score).The nomograms for the prediction of EAD and EAD type B had good discrimination[concordance index(C-index)=0.712(0.666-0.758),0.707(0.641-0.773)]and calibration[Hosmer-Lemeshow(HL)P=0.384,P=0.425]in the validation cohort.An increased operative time(>6 h)was associated with increased EAD and EAD type B incidence in the high-risk group(P=0.005,P=0.020,respectively).Conclusions:EAD type B was associated with decreased graft and patient survival rates.The novel nomograms effectively predicted the incidence of EAD and EAD type B in DCD LT patients.
