致心律失常性右心室心肌病患者心室晚电位与室性心动过速关系

目的探讨致心律失常性右心室心肌病(arrhythmogenic right ventricular dysplasia/cardiomyopathy,ARVD/C)合并室性心动过速与心室晚电位的关系。方法ARVD/C38例,男28例,女10例,年龄(35±15)岁。心电图检查进行信号叠加,记录心室晚电位量化参数:总QRS时限(total QRS duration,QRST)、QRS终末部位电压低于40μV时限(low potential terminal signals,LPS40)、QRS最后40ms电压方根均数(root mean square of the last 40 ms,RMS40);动态心电图检查记录室性心动过速和室性期前收缩。使用χ2及Mann-Whitney秩和检验统计。结果①心室晚电位阳性25例,其中室性心动过速18例;心室晚电位阴性13例,室性心动过速3例(P=0.004);②室性心动过速阳性21例,阴性17例,QRST:室性心动过速阳性组109～233(中位数147)ms,阴性组85～158(中位数104)ms(P=0.000);LPS40:阳性组15～158(中位数53)ms和阴性...     

Renal denervation as a second-line option in a patient with electrical storm resistant to medical treatment and conventional radiofrequency catheter ablation

Electrical storm (ES) represents a critical state of electrical instability. We describe a patient with coronary artery disease, mechanical aortic valve replacement, and reduced left ventricular function with recurrent ICD shocks. Despite medical treatment with beta-blocker and amiodarone, and after successful ablation of different VT morphologies in combination with substrate modification, ES could not be controlled. We performed renal denervation (RDN) to reduce arrhythmic burden. Thereafter, patient remained free from sustained and non-sustained VTs at 6-month follow-up. RDN is an effective second-line treatment option in patients in whom conventional catheter ablation and medical treatment failed to control the VTs.     

Profile of patients presenting with sustained ventricular tachycardia in a tertiary care center

Background and aimVentricular tachycardia (VT) represents the most frequent cause of sudden cardiac death. Information on clinical characteristics, acute management and outcome of patients with sustained VT is limited in our part of world. The aim of this study was to analyze the demography, hemodynamics, ECG features, underlying disease, mode of termination and outcome of patients presenting with VT.MethodsThis single center cohort study represents total of 107 patients of VT enrolled over 45 months.ResultsMean age was 45 years and 59 of the patients were males. Thirty three of these patients were hemodynamically unstable (31%) and 74 were stable (69%) Coronary artery disease was the most common etiological factor accounting for 39% of patients followed by non-ischemic cardiomyopathy. Determinants of hemodynamic instability were VT in course of acute myocardial infarction (8 out of fourteen) and polymorphic pattern of VT (13 out of 26). Spontaneous termination of VT occurred in seven patients, antiarrythmic drugs terminated VT in 53 of 67 patients and in remaining 45 patients VT was terminated with direct current (DC) cardioversion. Total of twenty three patients died during the hospital stay. Factors that contributed to mortality were old age, hemodynamic instability and low ejection fraction.ConclusionIschemic heart disease remains the leading cause of VT. Hemodynamically unstable VT occurs more frequently in acute myocardial infarction and polymorphic VT. Most effective method of VT termination is DC cardioversion. Old age, hemodynamic instability and ejection fraction contribute to overall mortality in VT.     

Clinical and electrophysiological differences between patients with arrhythmogenic right ventricular dysplasia and right ventricular outflow tract tachycardia.

AIMS: Radiofrequency catheter ablation is considered first line treatment for symptomatic patients with right ventricular outflow tract tachycardia (RVOT). The role of ablation in arrhythmogenic right ventricular dysplasia (ARVD) is more limited. As such, differentiating between the two conditions is essential. METHODS AND RESULTS: This study compared non-invasive findings, magnetic resonance images (MRI), invasive electrophysiological characteristics, results of ablation and long-term outcome in 50 consecutive patients with RVOT (33) or ARVD (17). Structural abnormalities were uniform in the ARVD group; in addition 18 (54%) of the RVOT tachycardia group had MRI abnormalities. At electrophysiological study the tachycardia in the ARVD group displayed features of re-entry in over 80%, but behaved with a triggered automatic basis in 97% with RVOT. Ablation was complete or partial success in 12 (71%) patients with ARVD and ventricular tachycardia (VT) recurred in eight (48%). In the RVOT patients, ablation was a complete success in 97% with recurrent VT in 6%. Long-term success in the RVOT patients was 95% in both patients with and without MRI abnormalities. CONCLUSIONS: Electrophysiological characterization can differentiate ARVD from RVOT. The finding of abnormalities on MRI does not have any bearing on arrhythmia mechanism, acute or long-term success of RFA.     

Isolated left ventricular non-compaction in association with ventricular tachycardia

A 32-year-old young male was found to have non-sustained, repetitive, monomorphic ventricular tachycardia of right bundle branch morphology during routine pre-anaesthetic evaluation for orthopaedic surgery. Echocardiography and left ventricular angiogram were suggestive of isolated non-compaction of left ventricular apex with systolic dysfunction. He was successfully managed with anti-arrhythmic drugs and had an uneventful 9-month follow-up. The index case is an unusual association of asymptomatic, non-sustained ventricular tachycardia with isolated ventricular non-compaction.     

His-Purkinje system re-entry in patients with clustering ventricular tachycardia episodes

Aims: Multiple arrhythmia re-inductions were recently shown in His-Purkinjesystem (HPS) ventricular tachycardia (VT). We hypothesized thatHPS VT was a frequent mechanism of repetitive or incessant VTand assessed diagnostic criteria to select patients likely tohave HPS VT. Methods and results: Consecutive patients with clustering VT episodes (>3 sustainedmonomorphic VT within 2 weeks) were included in the analysis.HPS VT was considered plausible in patients with (i) impairedleft ventricular function associated with dilated cardiomyopathyor valvular heart disease; or (ii) ECG during VT similar tosinus rhythm QRS or to bundle-branch block QRS. HPS VT was plausiblein 12 of 48 patients and HPS VT was demonstrated in 6 of 12patients (50%, or 13% of the whole study group). Median VT cyclelength was 318 ms (250–550). Catheter ablation was successfulin all six patients. Conclusion: His-Purkinje system VT is found in a significant number of patientswith repetitive or incessant VT episodes, and in a large proportionof patients with predefined clinical or electrocardiographiccharacteristics. Since it is easily amenable to catheter ablation,our data support the screening of all patients with repetitiveVT in this regard and an invasive approach in a selected groupof patients.     

孤立性左心室致密化不全心肌病患者的临床特点及相关因素预后分析

目的 分析孤立性致密化不全心肌病的临床特点及预后相关因素.方法 2008年5月至2011年4月在阜外心血管病医院确诊的34例孤立性左心室致密化不全患者分为室性心动过速（室速）组和非室速组,比较两组患者的左心室大小及左心室射血分数（LVEF）,随访患者临床事件.结果 入选时室速组和非室速组在左心室大小及LVEF平均值差异无统计学意义.平均随访2.92年,室速组死亡5例,非室速组死亡2例,死亡患者的平均左心室舒张末期内径（LVEDD）73mm,LVEF0.31.室速组有6例患者植入植入型心律转复除颤器（ICD）,随访期间4例发生持续性室速,其中3例患者ICD正确识别并电除颤治疗分别为2次、2次和8次;1例患者ICD正确识别并电除颤治疗1次,误识别2次.结论 孤立性左心室致密化不全患者预后与LVEDD、LVEF及室速相关.     

Electrical storm of monomorphic ventricular tachycardia after a cardiac-resynchronization-therapy-defibrillator upgrade.

In patients with significant left ventricular dysfunction and congestive heart failure despite optimal medical therapy, implantation of cardiac resynchronization therapy-defibrillation (CRT-D) devices has been shown to improve symptoms and mortality. In this report, we describe a case of a patient with ischaemic cardiomyopathy who developed incessant ventricular tachycardia (VT) after undergoing an upgrade from an implantable cardioverter defibrillator to a CRT-D device. The patient required multiple anti-arrhythmic agents, removal of the coronary sinus lead, and radiofrequency ablation to control VT. Thus, in rare patients, the CRT devices may potentially cause 'proarrhythmia' with serious consequences.     

Macroreentrant ventricular tachycardia mimicking focal ventricular tachycardia in a case with arrhythmogenic right ventricular cardiomyopathy

A 67-year-old man with ventricular tachycardia (VT) due to arrhythmogenic right ventricular cardiomyopathy (ARVC) underwent electrophysiologic testing. Electroanatomic mapping during the VT seemed to reveal a focal mechanism from near the tricuspid annulus (TA). Several radiofrequency applications delivered at the presumed focus resulted in termination but re-induction of the VT. Additional electroanatomic mapping underneath the TA led to the diagnosis of macroreentrant VT. Several RF applications targeting isolated and late potentials observed there during sinus rhythm eliminated the VT. In ARVC cases, detailed mapping underneath the TA should be performed to reveal the VT mechanism, resulting in suppressing VT recurrences. There was no financial support for this study.     

扩张型心肌病QT离散度增加与室性心动过速及心室颤动关系

目的探讨扩张型心肌病患者QT离散度(QTinterval dispersion,QTd)增加与室性心动过速、心室颤动的关系。方法回顾性分析41例扩张型心肌病患者心电图QTd及JT间期离散度(JT interval dispersion,JTd)。结果扩张型心肌病患者QTd和JTd在伴室性心动过速和心室颤动者分别为(101±35)ms或(100±33)ms;而无室性心动过速或心室颤动者分别为(54±18)ms,(57±20)ms,差异有统计学意义(P<0.05,P<0.01)。结论QTd或JTd增加,室性心动过速、心室颤动发生的可能增大,表明QTd或JTd可作为早期预测室性心动过速和心室颤动的一个重要参考指标。     

Management of electrical storm of unstable ventricular tachycardia in post myocardial infarction patients: A single centre experience

ObjectiveThis is a case series of consecutive patients with past myocardial infarction presenting with Electrical Storm (ES) of unstable ventricular tachycardia (VT) treated by a protocol directed algorithm.MethodsManagement protocol involved treatment of reversible causes, ventilatory & hemodynamic support, administration of antiarrhythmic drugs (AAD) & maximally tolerated doses of beta-blockers, stellate ganglionectomy and Radiofrequency ablation (RFA) guided by Electro Anatomic Mapping (EAM). Patients were followed up periodically with review of device data logs.ResultsThere were 12 patients (mean age = 61.38 ± 6.48 years & mean LVEF = 31.92 ± 4.23%). Presentation was recurrent ICD shocks (n = 5) or VT (n = 7). All were mechanically ventilated. Reversible causes were identified in 4 patients and appropriately addressed. Totally 8 patients underwent endocardial substrate modification by EAM & RFA. Endocardial LV Voltage mapping demonstrated a mean scar area of 70.04 ± 17.63 sq.cm (27.04 ± 6.20% of mapped area). The electrograms targeted for ablation included late potentials, fractionated electrograms, double potentials and channels within the scar. Two patients had stellate ganglionectomy in addition. Ten patients (83.3%) survived to discharge, all of whom are alive at a follow up of 30.12 ± 19 months free of ES. VT free survival at end of follow up was 80%. No patient had hospitalization related to VT. Single episode of VT recurrence was seen in 2 patients at 7 months and 1 year of follow up respectively.ConclusionIn post myocardial infarction patients presenting with ES and unstable VT, a protocol driven approach involving substrate modification targeting abnormal electrograms improves outcomes.     

室性心动过速患者QT离散度变化的临床意义

目的　探讨室性心动过速 (VT)患者 QT离散度 (QTd)变化的意义。方法　对正常对照组 (35例 )和 VT组 (31例 )记录 12导联同步心电图 ,人工测量 QT间期 ,计算 QTd。结果　与对照组相比 ,VT组 12导联QTd明显增加 (P<0 .0 1) ,但两组之间存在很大交叉 ,无法建立正常参考值 ;QT间期明显延长 (P<0 .0 1) ,两组QTmax多见于 V2 、V3、V4 和 V5导联 (分别为 75 .0 %、77.8% ) ,两组 QTmax、QTmin导联分布无显著差异 (P>0 .0 5 )。结论　 VT患者的 QTd不能代表心肌复极的区域性差异 ,仅可作为心肌复极异常简单、粗略的指标。