Most cases of sudden cardiac death are attributed to sustained ventricular tachyarrhythmias(VTs), triggered by acute coronary occlusion. Autonomic dysfunction, an important arrhythmogenic mechanism in this setting, is...Most cases of sudden cardiac death are attributed to sustained ventricular tachyarrhythmias(VTs), triggered by acute coronary occlusion. Autonomic dysfunction, an important arrhythmogenic mechanism in this setting, is being actively investigated, aiming at the advent of preventive strategies. Recent experimental studies have shown vagal withdrawal after anterior myocardial infarction, coinciding with high incidence of VTs, followed by more gradual sympathetic activation coinciding with a second arrhythmia peak. This article summarizes recent knowledge on this intriguing topic, generating hypotheses that can be investigated in future experimental and clinical studies.展开更多
Background Implantable cardioverter defibrillator （ICD） is the only effective therapy in patients with life threatening ventricular arrhythmias. Inappropriate detection and therapy by ICDs are the most common causes...Background Implantable cardioverter defibrillator （ICD） is the only effective therapy in patients with life threatening ventricular arrhythmias. Inappropriate detection and therapy by ICDs are the most common causes of side effects that affect the quality of life in ICD recipients. This study evaluated the incidence and causes of inappropriate detection and therapy by ICDs in patients in our hospital. Methods From January 2000 to December 2005, fifty patients who received ICD implantation for ventricular arrhythmias for prevention of sudden cardiac death were evaluated in this study. Each ICD was programmed using clinical arrhythmic and cardiac data of the patient before discharge. Patients were followed up by standard schedule after implantation and all data retrieved from each device were collected and saved for further analysis. Results No arrhythmic event was detected in 12/50 （24%） patients during the period of follow-up. Among the remaining patients, 11 （22%） experienced inappropriate detections and therapies during follow-up in this study. ICD detected 383 ventricular tachyarrhythmia （VT） and 108 ventricular fibrillation （VF） episodes and delivered 678 therapies. In VT group, ICD delivered 413 antitachycardiac pacings （ATPs） and 118 shocks, among which 78 ATPs and 9 shocks were initiated by 55/383 （14.3%） inappropriate detections. In VF group ICD delivered 147 shocks, among which 56 shocks were initiated by 28/108 （26.9%） inappropriate detections. Overall, more than 50% of these episodes were caused by atrial fibrillation （AF） with rapid ventricular response, followed by electromagnetic or myopotential interference. In addition, most inappropriate therapies occurred within one year after ICD implantation. Conclusions About one fifth of patients experienced ICD inappropriate detection and therapy after implantation. The main cause was AF with rapid ventricular response, followed by electromagnetic or myopotential interference.展开更多
Objective:Sudden cardiac death(SCD)and malignant ventricular arrhythmia(VA)are increasingly recognized as important issues for people living with a Fontan circulation,but data are lacking.We sought to characterize the...Objective:Sudden cardiac death(SCD)and malignant ventricular arrhythmia(VA)are increasingly recognized as important issues for people living with a Fontan circulation,but data are lacking.We sought to characterize the cohort who had sudden cardiac death,most likely related to VA and/or documented VA in the Australia and New Zealand Fontan Registry including risk factors and clinical outcomes.Methods:A retrospective cohort study was performed.Inclusion criteria were documented non-sustained ventricular tachycardia,sustained ventricular tachycardia,ventricular fibrillation,resuscitated cardiac arrest or SCD>30 days post-Fontan completion.Results:Of 1611 patients,20(1.2%)had VA;14(1.0%)had VA without SCD and 6(<1%)had SCD(6%of all deaths recorded in Registry;5 of those had documented VA at the time of arrest and 1 was presumed to be VA-associated).The median age at first VA was 20.5(14–32)years,10(50%)were females,and the median age at Fontan operation was 8(4–17)years.On univariable analysis,hypoplastic left heart syndrome(p=0.03)and older age Fontan operation(p<0.001)were associated with VA.Earlier Fontan era(p<0.003),atriopulmonary Fontan(p<0.001),pre-Fontan atrioventricular valve repair(p=0.013)pre-or post-Fontan atrial arrhythmia(p=0.010)were associated with SCD.Patients with VA had a 3 times higher risk of death or heart transplant(HR 3.27(1.19,8.98),p=0.02).Conclusions:A proportion of people living with a Fontan circulation have malignant VA.Routine VA screening in this cohort is essential.More data are needed to aid risk stratification.展开更多
Purpose: To investigate the alteration of left ventricular function in subjects with persistent atrial tachyarrhythmia induced cardiomyopathy (TIC) undergoing radiofrequency ablation, and to study the pathogenesis and...Purpose: To investigate the alteration of left ventricular function in subjects with persistent atrial tachyarrhythmia induced cardiomyopathy (TIC) undergoing radiofrequency ablation, and to study the pathogenesis and effective treatment of TIC. Methods: A total of 25 cases with persistent atrial tachyarrhythmia and impaired left ventricular systolic function were studied (16 men and 9 women, aged 53.3 ± 15.2 years), and all subjects underwent electrophysiological study and radiofrequency ablation of atrial tachyarrhythmia under the guidance of CARTO system during 2006.9-2011.8. Indexes related to cardiac function, including left ventricular end diastolic diameter (LVEDD), left ventricular ejection fraction (LVEF), New York Heart Association functional classification (NYHA class), 6 minutes walking test (6MWT), N-terminal pro-brain natriuretic peptide (BNP) and 24 hours average heart rate (AHR), were analyzed at the time point of 7 days, 3 and 6 months after the procedure as well as 1 day before ablation. Results: No refractory atrial arrhythmia recurred in all cases after ablation, compared with LVEDD (51.7 ± 4.5 mm), LVEF (39.0% ± 4.3%), number of patients with NYHA class IV and III (n = 17), 6MWT (212 ± 56 m), BNP (3622 ± 1860 ng/L) and AHR (112.5 ± 23.2 bpm) before ablation, the index of LVEDD (45.2 ± 3.3 mm;41.7 ± 2.5 mm;40.5 ± 3.1 m), BNP (2429 ± 1355 ng/L;1530 ± 866 ng/L;1300 ± 520 ng/L), total number of patients of NYHA class IV and III (n = 11;3;2) and AHR (73.3 ± 15.3 bpm;68.7 ± 13.5 bpm;66.3 ± 13.6 bpm) significantly decreased (P < 0.05), LVEF (45.6 ± 3.5%;51.5 ± 2.7%;53.5 ± 3.1%) and 6MWT (262 ± 47 m;305 ± 37 m;313 ± 41 m) greatly increased (P < 0.05)in 7 days, 3 and 6 months after ablation respectively. There was a statistical difference between 7 days and 3 or 6 months after ablation in above-mentioned indexes (P < 0.05) except AHR (P > 0.05), no significant difference existed between 3 and 6 months in all indexes (P > 0.05). Conclusion: long-lasting atrial arrhythmia with rapid ventricular response could impair left ventricle function, which could be reversed within weeks after successful ablation and restoration of sinus rhythm.展开更多
目的报告应用Carto 3电解剖标测系统指导射频消融治疗室性心律失常中的初步体验。方法采用Carto 3与CartoXP系统,以单一专用导管行心室电解剖重建,激动顺序、起搏与拖带标测,实施射频消融。观察消融的即刻成功率、成功靶点的分布、并发...目的报告应用Carto 3电解剖标测系统指导射频消融治疗室性心律失常中的初步体验。方法采用Carto 3与CartoXP系统,以单一专用导管行心室电解剖重建,激动顺序、起搏与拖带标测,实施射频消融。观察消融的即刻成功率、成功靶点的分布、并发症,手术时间及X线曝光时间、随访复发情况。比较Carto 3与CartoXP系统两组数据。结果共入选22例患者,每组各11例,Carto 3组即刻成功11例,成功消融部位:右室流出道间隔部5例,右室流出道游离壁2例,三尖瓣环1例,主动脉二尖瓣连接处1例,左后分支处1例,右室流出道游离壁+左冠窦1例。CartoXP组即刻成功11例,成功消融靶点均位于右室流出道,两组均未见并发症。术后随访1～6个月无1例复发。Carto 3组与CartoXP组比较,手术时间(57±29 min vs 62±10 min,P<0.01)与X线投照时间(5.23±5.42 min vs 8.45±2.33 min,P<0.01)明显缩短。结论应用Carto 3电解剖标测系统可快速重建心脏电解剖结构,提高消融治疗室性心律失常的效率。展开更多
Objective： To evaluate the arrhythmogenic effects of dismantling cadherin-mediated adhesion by recombinant mouse aminopeptidase N （rmAPN） in murine hearts. Methods： rmAPN was incubated with cultured neonatal rat c...Objective： To evaluate the arrhythmogenic effects of dismantling cadherin-mediated adhesion by recombinant mouse aminopeptidase N （rmAPN） in murine hearts. Methods： rmAPN was incubated with cultured neonatal rat cardiomyocytes as well as being infused in adult mice. The cell-cell connections were immunolabelled and observed by laser confocal microscopy. Disruption of the N-terminal of N-cadherin （N-cad） was detected by western blot and quantitative immunofluorescence. The risk of inducible ventricular tachyarrhythmia was evaluated in mice by an electrophysiological study. Results： Disrupted cell-cell contact was observed in cultured neonatal rat cardiomyocytes in response to 30-40 ng/μL rmAPN. Loss of the N-terminal in N-cad and altered distribution of connexin 43 （Cx43） were observed in hearts from rmAPN-infused mice. In addition, a reduction of phosphorylated Cx43 was also detected concomitant with redistribution of Cx43. Electrophysiological studies of rmAPN-infused mice showed prolonged QRS duration and increased inducibility of ventricular tachycardias. Conclusion： Disruption of N-cad by rmAPN contributes to gap junction remodeling and may elicit arrhythmogenic effects. The disorder of adherent junctions by proteolytic enzymes may play an important role in arrhythmogenic mechanisms in correlated diseases.展开更多
文摘Most cases of sudden cardiac death are attributed to sustained ventricular tachyarrhythmias(VTs), triggered by acute coronary occlusion. Autonomic dysfunction, an important arrhythmogenic mechanism in this setting, is being actively investigated, aiming at the advent of preventive strategies. Recent experimental studies have shown vagal withdrawal after anterior myocardial infarction, coinciding with high incidence of VTs, followed by more gradual sympathetic activation coinciding with a second arrhythmia peak. This article summarizes recent knowledge on this intriguing topic, generating hypotheses that can be investigated in future experimental and clinical studies.
文摘Background Implantable cardioverter defibrillator （ICD） is the only effective therapy in patients with life threatening ventricular arrhythmias. Inappropriate detection and therapy by ICDs are the most common causes of side effects that affect the quality of life in ICD recipients. This study evaluated the incidence and causes of inappropriate detection and therapy by ICDs in patients in our hospital. Methods From January 2000 to December 2005, fifty patients who received ICD implantation for ventricular arrhythmias for prevention of sudden cardiac death were evaluated in this study. Each ICD was programmed using clinical arrhythmic and cardiac data of the patient before discharge. Patients were followed up by standard schedule after implantation and all data retrieved from each device were collected and saved for further analysis. Results No arrhythmic event was detected in 12/50 （24%） patients during the period of follow-up. Among the remaining patients, 11 （22%） experienced inappropriate detections and therapies during follow-up in this study. ICD detected 383 ventricular tachyarrhythmia （VT） and 108 ventricular fibrillation （VF） episodes and delivered 678 therapies. In VT group, ICD delivered 413 antitachycardiac pacings （ATPs） and 118 shocks, among which 78 ATPs and 9 shocks were initiated by 55/383 （14.3%） inappropriate detections. In VF group ICD delivered 147 shocks, among which 56 shocks were initiated by 28/108 （26.9%） inappropriate detections. Overall, more than 50% of these episodes were caused by atrial fibrillation （AF） with rapid ventricular response, followed by electromagnetic or myopotential interference. In addition, most inappropriate therapies occurred within one year after ICD implantation. Conclusions About one fifth of patients experienced ICD inappropriate detection and therapy after implantation. The main cause was AF with rapid ventricular response, followed by electromagnetic or myopotential interference.
文摘Objective:Sudden cardiac death(SCD)and malignant ventricular arrhythmia(VA)are increasingly recognized as important issues for people living with a Fontan circulation,but data are lacking.We sought to characterize the cohort who had sudden cardiac death,most likely related to VA and/or documented VA in the Australia and New Zealand Fontan Registry including risk factors and clinical outcomes.Methods:A retrospective cohort study was performed.Inclusion criteria were documented non-sustained ventricular tachycardia,sustained ventricular tachycardia,ventricular fibrillation,resuscitated cardiac arrest or SCD>30 days post-Fontan completion.Results:Of 1611 patients,20(1.2%)had VA;14(1.0%)had VA without SCD and 6(<1%)had SCD(6%of all deaths recorded in Registry;5 of those had documented VA at the time of arrest and 1 was presumed to be VA-associated).The median age at first VA was 20.5(14–32)years,10(50%)were females,and the median age at Fontan operation was 8(4–17)years.On univariable analysis,hypoplastic left heart syndrome(p=0.03)and older age Fontan operation(p<0.001)were associated with VA.Earlier Fontan era(p<0.003),atriopulmonary Fontan(p<0.001),pre-Fontan atrioventricular valve repair(p=0.013)pre-or post-Fontan atrial arrhythmia(p=0.010)were associated with SCD.Patients with VA had a 3 times higher risk of death or heart transplant(HR 3.27(1.19,8.98),p=0.02).Conclusions:A proportion of people living with a Fontan circulation have malignant VA.Routine VA screening in this cohort is essential.More data are needed to aid risk stratification.
文摘Purpose: To investigate the alteration of left ventricular function in subjects with persistent atrial tachyarrhythmia induced cardiomyopathy (TIC) undergoing radiofrequency ablation, and to study the pathogenesis and effective treatment of TIC. Methods: A total of 25 cases with persistent atrial tachyarrhythmia and impaired left ventricular systolic function were studied (16 men and 9 women, aged 53.3 ± 15.2 years), and all subjects underwent electrophysiological study and radiofrequency ablation of atrial tachyarrhythmia under the guidance of CARTO system during 2006.9-2011.8. Indexes related to cardiac function, including left ventricular end diastolic diameter (LVEDD), left ventricular ejection fraction (LVEF), New York Heart Association functional classification (NYHA class), 6 minutes walking test (6MWT), N-terminal pro-brain natriuretic peptide (BNP) and 24 hours average heart rate (AHR), were analyzed at the time point of 7 days, 3 and 6 months after the procedure as well as 1 day before ablation. Results: No refractory atrial arrhythmia recurred in all cases after ablation, compared with LVEDD (51.7 ± 4.5 mm), LVEF (39.0% ± 4.3%), number of patients with NYHA class IV and III (n = 17), 6MWT (212 ± 56 m), BNP (3622 ± 1860 ng/L) and AHR (112.5 ± 23.2 bpm) before ablation, the index of LVEDD (45.2 ± 3.3 mm;41.7 ± 2.5 mm;40.5 ± 3.1 m), BNP (2429 ± 1355 ng/L;1530 ± 866 ng/L;1300 ± 520 ng/L), total number of patients of NYHA class IV and III (n = 11;3;2) and AHR (73.3 ± 15.3 bpm;68.7 ± 13.5 bpm;66.3 ± 13.6 bpm) significantly decreased (P < 0.05), LVEF (45.6 ± 3.5%;51.5 ± 2.7%;53.5 ± 3.1%) and 6MWT (262 ± 47 m;305 ± 37 m;313 ± 41 m) greatly increased (P < 0.05)in 7 days, 3 and 6 months after ablation respectively. There was a statistical difference between 7 days and 3 or 6 months after ablation in above-mentioned indexes (P < 0.05) except AHR (P > 0.05), no significant difference existed between 3 and 6 months in all indexes (P > 0.05). Conclusion: long-lasting atrial arrhythmia with rapid ventricular response could impair left ventricle function, which could be reversed within weeks after successful ablation and restoration of sinus rhythm.
文摘目的报告应用Carto 3电解剖标测系统指导射频消融治疗室性心律失常中的初步体验。方法采用Carto 3与CartoXP系统,以单一专用导管行心室电解剖重建,激动顺序、起搏与拖带标测,实施射频消融。观察消融的即刻成功率、成功靶点的分布、并发症,手术时间及X线曝光时间、随访复发情况。比较Carto 3与CartoXP系统两组数据。结果共入选22例患者,每组各11例,Carto 3组即刻成功11例,成功消融部位:右室流出道间隔部5例,右室流出道游离壁2例,三尖瓣环1例,主动脉二尖瓣连接处1例,左后分支处1例,右室流出道游离壁+左冠窦1例。CartoXP组即刻成功11例,成功消融靶点均位于右室流出道,两组均未见并发症。术后随访1～6个月无1例复发。Carto 3组与CartoXP组比较,手术时间(57±29 min vs 62±10 min,P<0.01)与X线投照时间(5.23±5.42 min vs 8.45±2.33 min,P<0.01)明显缩短。结论应用Carto 3电解剖标测系统可快速重建心脏电解剖结构,提高消融治疗室性心律失常的效率。
基金supported by a grant from Health Department of Jiangsu Province(No.RC2007041)
文摘Objective： To evaluate the arrhythmogenic effects of dismantling cadherin-mediated adhesion by recombinant mouse aminopeptidase N （rmAPN） in murine hearts. Methods： rmAPN was incubated with cultured neonatal rat cardiomyocytes as well as being infused in adult mice. The cell-cell connections were immunolabelled and observed by laser confocal microscopy. Disruption of the N-terminal of N-cadherin （N-cad） was detected by western blot and quantitative immunofluorescence. The risk of inducible ventricular tachyarrhythmia was evaluated in mice by an electrophysiological study. Results： Disrupted cell-cell contact was observed in cultured neonatal rat cardiomyocytes in response to 30-40 ng/μL rmAPN. Loss of the N-terminal in N-cad and altered distribution of connexin 43 （Cx43） were observed in hearts from rmAPN-infused mice. In addition, a reduction of phosphorylated Cx43 was also detected concomitant with redistribution of Cx43. Electrophysiological studies of rmAPN-infused mice showed prolonged QRS duration and increased inducibility of ventricular tachycardias. Conclusion： Disruption of N-cad by rmAPN contributes to gap junction remodeling and may elicit arrhythmogenic effects. The disorder of adherent junctions by proteolytic enzymes may play an important role in arrhythmogenic mechanisms in correlated diseases.
