Prognosis in Patients with Left Ventricular Dysfunction and Ventricular Tachycardia Following Programmed Ventricular Stimulation

We performed programmed ventricular stimulation on 69 patients with left ventricular ejection dysfunction (ejection fraction < 50%) and clinically recognized ventricular tachycardia including 28 patients with sustained ventricular tachycardia and 41 patients with nonsustained ventricular tachycardia. An inducible arrhythmia (> 6 beats ventricular tachycardia) was found in 74% of patients. Patients with clinically sustained arrhythmias were frequently inducible (89%) with a high incidence of inducible monomorphic ventricular tachycardia (82%). Patients with clinically nonsustained ventricular tachycardia had a lower rate of inducibility (63%) including a high incidence of inducible polymorphic ventricular tachycardia (27%). Inducible patients with left ventricular dysfunction and ventricular tachycardia had a low incidence of electrophysiologically demonstrated effective drug therapy (16%). However, if an effective drug was found, the prognosis was good. Empirical drug therapy was associated with a poor prognosis in inducible and noninducible patients. Finally, an unfavorable prognosis was associated with a clinically sustained arrhythmia, a lower ejection fraction, and the presence of a left ventricular aneurysm. An inducible arrhythmia did not predict an unfavorable course. Indeed, patients with noninducible ventricular tachycardia in this group of patients were still at risk for sudden cardiac death.     

Frequent Premature Ventricular Complexes Originating from the Right Ventricular Outflow Tract Are Associated with Left Ventricular Dysfunction

Background : Recent case series have shown reversal of left ventricular (LV) dysfunction after catheter ablation of frequent premature ventricular complexes (PVCs) originating from the right ventricular outflow tract (RVOT). We conducted a retrospective study to evaluate the prevalence of patients with frequent RVOT PVCs (≥10 per hour) and LV dysfunction. Methods : RVOT PVC was defined as PVC with left bundle branch block morphology and inferior axis on a 12‐lead ECG. We included patients with frequent RVOT PVCs on 24‐hours Holter monitor who had a recent evaluation of LV function. Patients with structural heart disease, including obstructive coronary artery disease, were excluded. Patients were divided into three groups based on the number of PVCs (<1000/24 hour, 1000–10,000/24 hour, ≥10,000/24 hour), and the prevalence of LV dysfunction was evaluated in each group. Results : Our analysis included 108 patients: 24 patients had <1000PVCs/24 hour, 55 patients had 1000–10,000PVCs/24 hour, and 29 patients had ≥10,000PVCs/24 hour. The prevalence of LV dysfunction was 4%, 12%, and 34%, respectively (P = 0.02). With logistic regression analysis, non‐sustained ventricular tachycardia was an independent predictor of LV dysfunction with odds ratio of 3.6 (1.3–10.1). Conclusion : We demonstrated a significant association between frequent RVOT PVCs and LV dysfunction in patients without structural heart disease.     

Case Report: Adenosine Induced Ventricular Fibrillation in a Patient with Stable Ventricular Tachycardia

Adenosine is frequently used in emergency departments and intensive care units for the termination of narrow complex tachycardias. Recently its utility in terminating wide complex tachycardias has been reported in the literature. Adenosine is generally felt to be a safe medication even though its proarrhythmic effects in the setting of narrow complex or supraventricular tachycardias have been well documented. Herein, we describe the first case to our knowledge of adenosine inducing ventricular fibrillation in a patient with a stable wide complex tachycardia that was subsequently proven to be ventricular tachycardia at electrophysiologic study.     

Idiopathic Left Ventricular Aneurysm: An Unusual Substrate of Ventricular Fibrillation and Ventricular Tachycardia

Idiopathic left ventricular aneurysm (LVA) is a very rare clinical condition. This article describes a patient with idiopathic LVA associated with episodes of ventricular tachycardia and ventricular fibrillation. Clinical and instrumental examinations did not reveal the pathogenesis of the aneurysm. The malignant clinical course suggests that an aggressive antiarrhythmic treatment, including ICD implantation, may be warranted.     

单纯收缩期高血压患者左心室肥厚与室性心律失常的关系

目的探讨单纯收缩期高血压的病人左室肥厚与心律失常的关系。方法采用２４ｈ动态心电图和彩色多普勒超声观察患者左室肥厚及心律失常的发生情况，并观察单纯收缩期高血压与舒张期高血压左室结构改变。结果左室肥厚组室性心律失常发生率明显高于非左室肥厚组（Ｐ＞０．０１），单纯收缩期高血压组左室肥厚高于舒张期高血压组。结论左室肥厚可使室性心律失常发生率增加，收缩压增高较舒张压增高更易导致左室肥厚。     

Septal Ventricular Tachycardia with Alternating LBBB–RBBB Morphology in Isolated Ventricular Noncompaction

Alternating VT Morphology in IVNC. Knowledge on ventricular tachycardia (VT) in isolated ventricular noncompaction (IVNC) is limited. We report on a patient with IVNC who presented with cardiogenic shock due to an incessant drug‐resistant VT that was cured by radiofrequency ablation. The VT had characteristics of a deep septal focal arrhythmia, which was distinctive by ablation‐induced alternation of the rightward and leftward exits, and was difficult to ablate from either side of the ventricular septum. (J Cardiovasc Electrophysiol, Vol. 21, pp. 704‐707, June 2010)     

高血压左室肥厚与室性心律失常的研究进展

研究表明高血压左室肥厚的患者室性心律失常,尤其是复杂性室性心律失常发生率增高,目前认为主要与左室重构、心肌缺血、肥厚心肌的电生理改变、神经内分泌因子分泌异常等多种因素有关。在对高血压病的患者进行降压治疗的同时逆转左室肥厚能减少室性心律失常的发生,肾素-血管紧张素系统抑制剂因在此方面作用显著而倍受关注。     

Hypertrophic Cardiomyopathy with Right Ventricular Outflow Tract and Left Ventricular Intracavitary Obstruction

Obstruction of the right ventricular outflow tract (RVOT) is a rare finding in hypertrophic cardiomyopathy (HCM) patients unlike left ventricular outflow tract (LVOT) obstruction. Although there are guidelines that aid in clinical decision making in patients with LVOT obstruction, there are none addressing RVOT obstruction. As RVOT obstruction may pose serious clinical implications similar to LVOT obstruction, appropriate medical and surgical management is very important. A unique phenotype of HCM with RVOT obstruction in conjunction with left ventricle (LV) intracavitary obstruction is discussed.     

原发性醛固酮增多症患者与左心室肥厚

目的探讨原发性醛固酮增多症（原醛）及其主要亚型：腺瘤型和增生型的左室肥厚情况。方法入选确诊原醛患者250例。其中142例行分侧肾上腺静脉取血，分为原醛腺瘤组68例，原醛增生组74例，选取同期年龄、性别、24小时平均血压相匹配的原发性高血压（EH）患者246例作为对照，所有入选者记录一般临床资料和生化指标，并行超声心动图检查。结果1）左室舒张末期内径原醛组[（49．6&#177;4．3）mm]高于EH组[（48．3&#177;4．2）mm，P〈0．053，原醛组左室后壁厚度[原醛组（10．5&#177;2．2）mm vs EH组（9．9&#177;1．1）mm]、左室质量（LVM）[原醛组（232．2&#177;75．1）g vs EH组（207．5&#177;46．6）g]、左室质量指数（LVMI）[原醛组（131．9&#177;37．4）g／m^2 vs EH组（118．3&#177;23．7）g／m^2]显著高于EH组（P均〈0．01）。2）在原醛组中LVMI与收缩压及立位血浆醛固酮独立相关。3）1级高血压中原醛组的LVMI高于EH组，但差异无统计学意义（P〉0．05）；2级、3级高血压中，原醛组的LVMI高于EH组（P〈0．05或P〈0．01）。4）左室后壁厚度[原醛组（10．8&#177;3．0）gVSEH组（10．3&#177;1．3）g，P〈0．053；、LVM[原醛组（249．5&#177;81．7）g vs EH组（219．4&#177;67．7）g，P〈0．01]、LVMI[原醛组（139．9&#177;41．0）g／m^2 vs EH组（125．1&#177;32．9），P〈0．01]原醛腺瘤组显著高于原醛增生组。5）左室肥厚在EH组、原醛腺瘤组和增生组的构成比分别为42．7％，63．2％和43．2％，3组之间差异有统计学意义（P=0．009）。结论原醛患者左室肥厚的发病率高于EH患者，其中以原醛腺瘤组更为严重。     

Upgrading Pacemaker Patients with Right Ventricular Apical Pacing to Right Ventricular Septal Pacing Improves Left Ventricular Performance and Functional Capacity

Background : Right ventricular (RV) apical pacing results in abnormal left ventricular (LV) electrical and mechanical activation and is associated with an increased risk of developing heart failure. Chronic RV septal pacing has been shown to be superior to RV apical pacing in newly implanted patients. However, whether RV septal pacing can reverse deleterious effects of RV apical pacing remain unclear.
Methods : We evaluated the effects of RV septal pacing on LV performance and functional capacity before and at 18 months after device replacement in 12 patients with previously permanent RV apical pacing and in 12 control patients that continued RV apical pacing. All patients underwent radionuclide ventriculography and 6-minute hallwalk (6-MHW) test before replacement (baseline) and at 18 months afterward to determine changes in LV performance and functional capacity, respectively.
Results : After RV septal upgraded, there was a significant decrease in paced QRS duration (171.2 ± 3.9 ms to 160.4 ± 3.5 ms, P = 0.0016), increase in LV ejection fraction (55.2 ± 2.6% vs 60.4 ± 2.9%, P = 0.0002), the peak ventricular filling rate (2.60 ± 0.13 s⁻¹ vs 3.01 ± 0.14 s⁻¹, P = 0.046), and 6-MHW (308.2 ± 31.6 m vs 355.5 ± 34.2 m, P = 0.015) at 18 months compared with baseline. No changes in these parameters were observed in the control group (P > 0.05).
Conclusion : RV septal pacing upgraded improves LV systolic and diastolic function and functional capacity in patients with previously permanent RV apical pacing. These findings suggest that RV septal pacing can reverse the deleterious effects of RV apical pacing in patients who required permanent ventricular pacing.     

Ablation of Ventricular Arrhythmias in Arrhythmogenic Right Ventricular Dysplasia

VT Ablation in Right Ventricular Dysplasia. Arrhythmogenic right ventricular dysplasia (ARVD) is a genetically determined myocardial disease characterized by fibrofatty replacement of the right ventricular wall. Ventricular tachyarrhythmias can be seen in the early stages of the disease, which is one of the most important causes of sudden death in young healthy individuals. Radiofrequency (RF) catheter ablation is an option for the treatment of medically refractory ventricular arrhythmias and it has shown to successfully abolish recurrent ventricular tachycardias (VT) as well as reduce the frequency in defibrillator therapies. However, variable acute and long‐term success rates have been reported. The current mapping and ablation techniques include activation and entrainment mapping during tolerated VT and substrate ablation using 3‐dimensional electroanatomic mapping systems. This article aims at providing a comprehensive review of RF catheter ablation of ventricular arrhythmias in the context of ARVD. (J Cardiovasc Electrophysiol, Vol. 21, pp. 473‐14, April 2010)     

The Effects of Simvastatin on Left Ventricular Hypertrophy and Left Ventricular Function in Patients with Essential Hypertension

This study is to evaluate the effects of Simvastatin on left ventricular hypertrophy and left ventricular function in patients with essential hypertension. Untreated or noncompliance with drug treatment patients with simple essential hypertension were treated with a therapy on the basis of using Telmisartan to decrease blood pressure (BP). There were 237 patients who had essential hypertension combined with left ventricular hypertrophy as diagnosed by echocardiography, taken after their BPs were decreased to meet the values of the standard normal. Among them, there were only 41 out of the original 237 patients, 17.3%, who had simple essential hypertension combined with left ventricular hypertrophy without any other co-existing disease. They were the patients selected for this study. All patients were randomly, indiscriminately divided into two groups: one was the control group (Group T), treated with the Telmisartan-based monotherapy; the other was the target group (Group TS), treated with the Telmisartan-based plus simvastatin therapy. The changes of left ventricular hypertrophy and left ventricular function were rediagnosed by echocardiography after 1 year. The results we obtained from this study were as follows: (i) The average BPs at the beginning of the study, of simple essential hypertension combined with left ventricular hypertrophy, were high levels (systolic blood pressure (SBP) 189.21 ± 19.91 mm Hg, diastolic blood pressure 101.40 ± 16.92 mm Hg). (ii) The Telmisartan-based plus simvastatin therapy was significantly effective in lowering the SBP (128.26 ± 9.33 mm Hg vs. 139.22 ± 16.34 mm Hg). (iii) After the 1-year treatment, the parameters of left ventricular hypertrophy in both groups were improved. Compared to group T, there were no differences in the characteristics of the subjects, including interventricular septum, left ventricular mass, left ventricular mass index, ejection fraction, left atrium inner diameter at baseline. The patients’ interventricular septum (Group TS 10.30 ± 1.80 mm vs. Group T 10.99 ± 1.68 mm, P < .05), LVM (Group TS 177.43 ± 65.40 g vs. Group T 181.28 ± 65.09 g, P < .05), and LVMI (Group TS 100.97 ± 37.33 g/m² vs. Group T 106.54 ± 27.95 g/m², P < .05), all dropped more prominently (P < .05) in group TS; the ejection fraction rose more remarkably in group TS (Group TS: 57.50 ± 16.41% to 65.43 ± 11.60%, P < .01 while showing no change in Group T); the left ventricular hypertrophy reversed more significantly and the left ventricular systolic function improved more. (iv) The left atrium inner diameter of Group TS decreased (P < .01), the ratio of E/A, which indicates the left ventricular diastolic function, continued to drop further, showing no change to the trend of left ventricular diastolic function declination. Patients who have hypertension with left ventricular hypertrophy usually suffer other accompanying diseases at the same time. Telmisartan-based plus Simvastatin treatment can significantly reduce SBP, reverse left ventricular hypertrophy, improve the left ventricular systolic function, but it has no effect on reversing the left ventricular diastolic function. This experiment indicated that Simvastatin can reverse left ventricular hypertrophy and improve left systolic function.     

左室重量指数与复杂性室性心律失常

目的探讨左室重量指数预测复杂性室性心律失常的临床价值。方法对１１６例轻、中度高血压病人行超声心动图和动态心电图监测。４０例健康人作对照组。结果复杂性室性心律失常发生率在左室重量指数法和左室实测值法左室肥厚组分别为３６．９％，１３．９％，二者差异显著（Ｐ＜０．０１）。结论左室重量指数法左室肥厚对预测复杂室性心律失常有重要价值。     

Spontaneous Variability of Ventricular Ectopic Activity in Patients with Sustained Ventricular Tachycardia and in Survivors of Cardiac Arrest

Background: Spontaneous variability of ventricular arrhythmia has been described in patients with chronic stable ventricular arrhythmias and in patients with chronic heart failure. However, no data are available on spontaneous variability in patients with sustained ventricular tachyarrhythmias. Thus, the present study was designed to prospectively determine the extent of spontaneous variability of ventricular arrhythmia in patients with sustained ventricular tachyarrhythmias and in survivors of cardiac arrest. Methods: Ventricular arrhythmia variability was determined in 470 patients (413 men, 57 women), age (mean ± SD) 64.6 ± 9.5 years with documented ventricular tachycardia (VT), cardiac arrest, or syncope who were prospectively enrolled in a randomized trial of the comparison of electrophysiological testing with Holter monitoring to predict antiarrhythmic drug efficacy. Coronary artery disease was present in 398 (85%) patients, and the mean left ventricular ejection fraction was 0.32 ± 0.13. They underwent two 24-hour ambulatory recordings separated by 1 day. Spontaneous variability was determined for total premature ventricular complexes (PVCs), pairs, and VT events. Results: Arithmetic mean of hourly total PVCs on day 1 was 315 ± 425. The 95% confidence limit of spontaneous reduction in total PVC count was 71%. Corresponding values for pairs, VT events of 3–15 beats, < 15 beats, or < 15 seconds were 72%, 80%, 94%, and 95%, respectively. The percentage increases in total PVCs, pairs, and VT events 3–15 beats, < 15 beats, and < 15 seconds were 243%, 259%, 397%, 1553%, and 1756%, respectively. The percentage reduction required to show a true drug effect was 63% for patients with an ejection fraction > 0.32 and 76% for those with an ejection fraction ltm 0.32 (P = 0.024). Patients who presented with unmonitored syncope showed less spontaneous variability than either patients with documented, sustained VT or cardiac arrest. Conclusions: Marked spontaneous variability of ventricular arrhythmias is observed in patients with sustained ventricular tachyarrhythmias. Variability is affected by the degree of left ventricular dysfunction. The lowest variability was observed in patients presenting with unmonitored syncope. Thus, large changes in arrhythmia frequency must be observed in this population, as in others, to be ascribed to drug effect.     

Ventricular Tachycardia in Patients with Impaired Left Ventricular Function: The Role of Propafenone

The combined occurrence of left ventricular dysfunction and -ventricular tachyarrhythmias portends a high annual mortality. Anti arrhythmic drugs can ameliorate ventricular arrhythmia and may reduce the risk of sudden cardiac death. We administered propafenone to 15 patients with ventricular tachyarrhythmias and left ventricular ejection fractions 40%. Propafenone significantly reduced isolated ventricular premature depolarizations, couplets, and ventricular tachycardia on ambulatory monitoring. Propafenone eliminated all exercise provocable ventricular tachycardia. Propafenone additionally abolished ventricular tachycardia inducible by programmed stimulation in 4 of 7 patients. In 8 patients studied before and during therapy, there was no significant change in left ventricular ejection fraction as determined by nuclear ventriculography. Propafenone was discontinued in 4 patients due to side effects. Seven patients receiving continuing propafenone therapy remain alive with only one patient suffering arrhythmia recurrence. Propafenone is an effective drug for the management of ventricular tachyarrhythmias and may be used for patients with impaired left ventricular function.     

The Clinical Significance of Nonsustained Ventricular Tachycardia in Patients with Sustained Ventricular Tachyarrhythmias

Background: Nonsustained ventricular tachycardia (NSVT) predicts mortality in several disorders but its significance in patients with sustained ventricular tachyarrhythmias is unknown. We analyzed the clinical features and outcome associated with NSVT (>; 3 beats at >; 100 beats/min) recorded on a 48-hour Holter in the absence of antiarrhythmic drugs. Methods: Patients enrolled in the ESVEM trial (n = 486) were grouped according to the duration of the longest recorded episode of NSVT, and in the second analysis, according to frequency of recorded episodes. Assessments were on an intention-to-treat basis. Results: Patients without NSVT were more likely to have ischemic heart disease and had significantly lower frequencies of single and paired premature ventricular complexes (PVCs). There were no significant differences with respect to age, sex, presenting arrhythmia, years since last myocardial infarction, functional class, or present ejection fraction. The cumulative probabilities of arrhythmia recurrence and all-cause mortality at 4 years in patients without NSVT (60%± 7% and 32%± 6%, respectively) were not significantly different than those of patients with NSVT (63%± 3% and 41%± 3%, respectively). Cox regression models indicated that ejection fraction and functional class were significant predictors of outcome, but variables based on the presence, duration, and frequency of recorded episodes of NSVT were not. Conclusions: NSVT is common in patients with spontaneous and inducible sustained ventricular tachyarrhythmias and at least 10 PVCs/hour (ESVEM enrollment criteria), but is not a significant predictor of arrhythmia recurrence, sudden death, or all-cause mortality in patients with these characteristics.     

Ventricular Fibrillation Resulting from Synchronized Internal Atrial Defibrillation in a Patient with Ventricular Preexcitation

VF After Synchronized Internal Atrial Defibrillation. This case describes ventricular proarrhythmia as a result of a synchronized internal atrial defibrillation shock in a 29-year-old man with Ebstein's anomaly referred for radiofrequency ablation of a right posterior accessory pathway. During the electrophysiologic study, atrial fibrillation was induced and 3/3 msec shocks of various strengths were delivered between two decapolar defibrillation catheters in the coronary sinus and right atrial appendage. A 2.0-J biphasic shock synchronized to an R wave after a short-long-short ventricular cycle length pattern with a preshock coupling interval of 245 msec induced ventricular fibrillation, which was externally defibrillated with 200 J. This observation has implications for the development of implantable atrial defibrillators.