Premature Ventricular Contractions and Non-sustained Ventricular Tachycardia: Association with Sudden Cardiac Death,Risk Stratification,and Management Strategies

Premature ventricular contractions (PVCs) and non-sustained ventricular tachycardia (NSVT) are frequently encountered and a marker of electrocardiomyopathy. In some instances, they increase the risk for sustained ventricular tachycardia, ventricular fibrillation, and sudden cardiac death. While often associated with a primary cardiomyopathy, they have also been known to cause tachycardia-induced cardiomyopathy in patients without preceding structural heart disease. Medical therapy including beta-blockers and class III anti-arrhythmic agents can be effective while implantable cardiac defibrillators (ICD) are indicated in certain patients. Radiofrequency ablation (RFA) is the preferred, definitive treatment in those patients that improve with anti-arrhythmic therapy, have tachycardia-induced cardiomyopathy, or have certain subtypes of PVCs/NSVT. We present a review of PVCs and NSVT coupled with case presentations on RFA of fascicular ventricular tachycardia, left-ventricular outflow tract ventricular tachycardia, and Purkinje arrhythmia leading to polymorphic ventricular tachycardia.     

Successful Right Ventricular Tachycardia Ablation in a Patient with Left Ventricular Non-compaction Cardiomyopathy

We report a case of a 67-year old male with a recent diagnosis of left ventricular noncompaction (LVNC), initially presenting with symptomatic ventricular ectopy and runs of non-sustained ventricular tachycardia (VT). This ventricular arrhythmia originated in a structurally normal right ventricle (RV) and was successfully localized and ablated with the aid of the three-dimensional mapping and remote magnetic navigation.     

Pseudo-polymorphic Ventricular Tachycardia in a 12-lead Holter Recording

We present an image of pseudo-polymorphic ventricular tachycardia recording on a 12-lead surface ECG Holter. Although at first glance the appearance of the recording resembled polymorphic ventricular tachycardia, careful investigation revealed normal electrocardiographic findings.     

Brugada ECG Pattern Unmasked by IV Flecainide in an Individual with Idiopathic Fascicular Ventricular Tachycardia

A 45-year old man presents with stable monomorphic ventricular tachycardia. He had previously been diagnosed with idiopathic fascicular ventricular tachycardia. Intravenous flecainide results in termination of his tachycardia but unmasks a latent type 1 Brugada ECG pattern not seen on his resting ECG. We discuss his subsequent management and the need to consider an alternative diagnosis in individuals with a Brugada type ECG pattern who present with stable monomorphic ventricular tachycardia.     

Ventricular tachycardia ablation in children

IntroductionThe ablation of ventricular tachycardia, including premature ventricular contractions, is an approved, albeit infrequent procedure in pediatric patients. Data are scarce regarding the outcomes of this procedure. The purpose of this study was to share a high-volume center experience and patient outcomes for catheter ablation of ventricular ectopy and ventricular tachycardia in pediatric population.MethodsData were retrieved from the institutional data bank. Outcomes over time were evaluated, and procedural details were compared.ResultsA total of 116 procedures were performed on 102 pediatric patients between July 2009 and May 2021 at the Rajaie Cardiovascular Medical and Research Center in Tehran, Iran. Ablation was not performed in 4 procedures (3.4%) due to high-risk substrates. Of the remaining 112 ablations performed, 99 (88.4%) were successful. However, one patient died due to a coronary complication. There were no significant differences observed in early ablation results based on patients' age, sex, cardiac anatomy, or ablation substrates (P > 0.05). Follow-up records were available for 80 procedures, and 13 (16.3%) of those experienced recurrence. During long-term follow-up, none of the variables mentioned above were statistically different between patients with or without arrhythmia recurrence.ConclusionThe overall success rate of pediatric ventricular arrhythmia ablation is favorable. We found no significant predictor for the procedural success rate concerning acute and late outcomes. Larger multicenter studies are needed to elucidate the predictors and outcomes of the procedure.     

Focal Monomorphic Ventricular Tachycardia As The First Manifestation Of Amyloid Cardiomyopathy

52-year-old patient presented with palpitation and well tolerated monomorphic ventricular tachycardia. He had normal echocardiogram and coronary angiogram 3 months prior to presentation. Surface EKG revealed regular wide-complex tachycardia with right bundle branch block morphology and right inferior axis. In conjunction with recent negative cardiac evaluation, this suggested idiopathic focal ventricular tachycardia from anterolateral basal left ventricle. CARTO based activation mapping confirmed the presence of VT focus in that area. Radiofrequency ablation at the site of perfect pacemap resulted in a partial suppression of the focus. Echocardiogram was subsequently performed because of progressive dyspnea. It revealed asymmetrical thickening of posterolateral left ventricle, with delayed enhancement on contrast magnetic resonance imaging. Fine needle aspiration of abdominal fat stained with Congo red confirmed the diagnosis of systemic AL amyloidosis due to IgG λ-light chain deposition. Consequently, the patient underwent placement of implantable defibrillator and hematopoetic stem cell transplantation. He remains in excellent functional status 18 months after presentation.     

Ventricular tachycardia in repaired double chambered right ventricle - identification of the substrate and successful ablation

A 35 year old female presented with recurrent ventricular tachycardia 5 years after she had undergone surgical repair of double chambered right ventricle. Electroanatomical mapping showed a localised scar in the apex with double potentials and good pace map. Ablation here resulted in non-inducibility of ventricular tachycardia. We hypothesise that the scarring in the apex is the result of sustained pressure overload and becomes arrhythmogenic similar to the apical scar in patients with mid-ventricular hypertrophic cardiomyopathy.     

特发性右心室流出道室性心律失常射频消融术后复发因素分析

目的:探讨特发性右心室流出道室性心律失常射频消融术后,患者室性心律失常复发的原因,旨在为进一步降低复发率提供线索。方法:1999年12月至2009年12月,在解放军总医院老年心血管内科住院行导管射频消融的特发性右心室流出道室性心律失常患者共145例(男55例,女90例),治疗终点为室性心律失常消失,不能被心室电刺激和静滴盐酸异丙肾上腺素诱发,术后1天复查动态心电图并电话随访观察疗效。结果:在145例患者中,即刻成功136例,成功率为93.8%。随访23.8±6.7月,共有9例患者复发,复发率为6.62%。9例复发患者再次行射频消融术的靶点局部激动(34.0±7.6 ms)明显早于第一次射频消融术(30.4±8.5 ms)(P<0.05);靶点起搏与自发心律失常体表心电图QRS波形的符合数(11.8±0.45)大于第一次射频消融术(11.1±0.78)(P<0.05);复发患者第一次手术在最早激动点处单极标测r波的出现比例大于第二次手术(P<0.05),再次手术均成功。结论:导管射频消融治疗特发性右心室流出道室性心律失常是有效、可行的方法。靶点标测欠精确是术后复发的主要原因。     

Ventricular arrhythmias.

Sudden cardiac death claims thousands of Canadians annually. Ventricular tachycardia and fibrillation account for up to 85% of these deaths. Identifying the patients at risk remains a major challenge. Those who have recurrent ventricular tachycardia or have been resuscitated from ventricular fibrillation are generally considered to be at highest risk. Although ventricular premature beats in the absence of previous ventricular tachycardia or fibrillation are not helpful in identifying such patients in most cases, they can indicate increased risk for sudden cardiac death in the presence of a structural cardiac abnormality, particularly recent myocardial infarction; however, the need for treatment in such cases is speculative and is being investigated. Treatment is mandatory for survivors of an episode of ventricular fibrillation and those with recurrent sustained ventricular tachycardia or torsade de pointes ventricular tachycardia. The approach to management is either invasive or noninvasive. Selection of an antiarrhythmic agent is facilitated by knowledge of some basic electrophysiologic features of the heart and of the classification of antiarrhythmic drugs. However, drug therapy has to be individualized on the basis of efficacy, left ventricular function and adverse effects or potential adverse effects of the drug. Amiodarone therapy or nonpharmacologic therapy should be considered if a suitable antiarrhythmic agent cannot be found.     

Normal Heart Ventricular Tachycardia Associated with Pregnancy: Successful Treatment with Catheter Ablation

Background

Normal heart ventricular arrhythmia occurring during pregnancy has been previously described. Whilst there are established reports of catheter ablation to treat supraventricular arrhythmia during pregnancy, there are no reports of ablation to treat ventricular tachycardia.

Case

We present the case of a 36 year old women, 31 weeks into an otherwise uncomplicated pregnancy, experiencing significant, troublesome and drug refractory tachycardia emanating from the right ventricular outflow tract.

Conclusion

We describe a successful radio frequency ablation in the third trimester of pregnancy.     

An Alternative Way to Reach the Epicardial Focus of the Left Ventricular Tachycardia in a Patient with Non-ischemic Cardiomyopathy

We report a case of a 69-year-old male with non-ischemic cardiomyopathy, having drug- and antitachycardia pacing-refractory ventricular tachycardia resulted in multiple ICD shocks. The sustained and intractable ventricular arrhythmia was mapped and ablated with the aid of the three-dimensional electroanatomic mapping system, initially performed but unsuccessful from the endocardial site then performed successfully from the epicardial site via the coronary sinus.     

Right Ventricular Endomyocardial Fibrosis Presenting With Ventricular Tachycardia And Apical Thrombus - An Interesting Presentation

Endomyocardial fibrosis is a progressive disease of unknown origin affecting children and young adults. It involves inflow portion of right and/or left ventricle and apex. It may be associated with thrombus. Literature regarding right ventricular endomyocardial fibrosis with thrombus is scarce. Here we report a rare case of right ventricular endomyocardial fibrosis presenting as ventricular tachycardia and echocardiographic evidence of apical thrombus. Interestingly there was no pulmonary involvement or evidence of deep venous thrombosis. This case also underscores the importance of urgent echocardiography in diagnosis of obscure cases of ventricular tachycardia.     

Ventricular Tachycardia Caused by Mesothelial Cyst

A 27 year-old- lady was evaluated due to recurrent ventricular tachycardia. After performing echocardiography and cardiac MRI, she was found to have large pericardial cyst. Pathologic examination confirmed it as mesothelial pericardial cyst. Up to our knowledge it is the first presentation of simple pericardial cyst as ventricular a tachycardia.     

Verapamil Sensitive Ventricular Tachycardia Associated With A Cardiac Hemangioma In The Right Ventricular Outflow Tract

Primary tumors of the heart are rare, but they are often associated with refractory arrhythmias. Vascular tumors of the heart comprise a small minority of primary cardiac tumors. In patients with structurally normal hearts, ventricular tachycardia (VT) originating from the right ventricular outflow tract (RVOT) can be sensitive to adenosine, vagal maneuvers, and calcium channel blockers. In this report, we describe a case of ventricular tachycardia originating from within a hemangioma in the RVOT that was ultimately controlled with verapamil.     

Ventricular tachycardia due to cardiac ischaemia: assessment by exercise electrocardiography

Although ventricular tachycardia is a well-known complication of myocardial ischaemia and may be provoked by exercise, many patients may appreciate only the angina and be unaware of the unduly rapid heart rate that precipitates it. Exercise testing is needed to show this arrhythmia and to enable treatment to be started.Twenty-three patients were found to have chronic ischaemic heart disease complicated by ventricular tachycardia. Six patients with old myocardial infarction had ventricular tachycardia at rest which required conversion to sinus rhythm; 17 patients developed ventricular tachycardia only when they exercised. In 12 of these 17 patients coronary angiography showed disease of the anterior descending branch of the left coronary artery; other vessels were usually also affected. Although beta-adrenergic blocking drugs increased exercise tolerance, ventricular tachycardia still occurred when the heart rate on exercise reached a level similar to that before treatment. In five patients coronary artery bypass surgery was performed because of angina and exercise-induced ventricular tachycardia. Exercise tolerance was increased in all three patients who underwent exercise tests after operation, and in two of these patients, both of whom were known to have patent grafts, ventricular tachycardia was abolished.If part of the beneficial effect of coronary bypass surgery is preventing life-threatening ventricular arrhythmias it is essential to detect these, and ambulatory monitoring and stress testing have a complementary role.     

Ischemic Ventricular Tachycardia Presenting as a Narrow Complex Tachycardia

This report describes a patient presenting with a narrow complex tachycardia in the context of prior myocardial infarction and impaired ventricular function. Electrophysiological studies confirmed ventricular tachycardia and activation and entrainment mapping demonstrated a critical isthmus within an area of scar involving the His-Purkinje system accounting for the narrow QRS morphology. This very rare case shares some similarities with upper septal ventricular tachycardia seen in patients with structurally normal hearts, but to our knowledge has not been seen previously in patients with ischemic heart disease.     

Polymorphic Ventricular Tachycardia Due to Acute Coronary Ischemia: A Case Report

Acute myocardial ischemia can cause ventricular tachycardia (VT) in patients with structurally normal heart. Contrary to the fact that in patients with chronic myocardial scarring the ventricular tachycardia is monomorphic, in patients with acute ischemia the ventricular tachycardia is polymorphic and is reversible with coronary revascularization.We are reporting a 40 year old male who presented with recurrent syncope due to polymorphic ventricular tachycardia in the context of normal QT interval in baseline ECG and normal left ventricular function without any evidence of myocardial injury. Due to recurrent fatal ventricular arrhythmia despite medical management, urgent coronary angiography was done which showed critical obstruction of right coronary artery (RCA). Considering the critical obstruction of RCA responsible for polymorphic VT, emergency PCI of RCA was done. After successful PTCA and stenting to RCA, he had another episode of polymorphic VT which was terminated with intravenous phenytoin. Seven days after the PCI, 24 hours Holter monitoring was done which showed normal sinus rhythm with infrequent ventricular premature complexes and no evidence of VT. He was asymptomatic at six months follow-up.     

Peripartum Cardiomyopathy Presenting With Ventricular Tachycardia: A Rare Presentation

A 25-year-old previously asymptomatic pregnant woman at 36 weeks'' gestation was noticed to have repetitive monomorphic ventricular tachycardia. A dilated left ventricle with moderately reduced systolic function was found on echocardiographic examination. This is a very rare presentation of peripartum cardiomyopathy (PPCMP) presenting with repetitive monomorphic ventricular tachycardia.     

兔右室流出道室速对L型钙通道α1c蛋白表达的影响

目的：通过建立右室流出道室速（RVOT-VT）的动物模型,以L型钙通道α1c蛋白作为观察指标,观察RVOT-VT时对L型钙通道α1c蛋白表达的影响,旨在探讨L型钙通道在RVOT-VT中的作用。方法：健康新西兰大耳白兔30只,随机分三组,分别为对照组（10只）、室速组（10只）、室速加维拉帕米干预组（10只）。采用免疫组织化学的方法对三组实验动物的右室流出道心肌组织进行L型钙通道cdc蛋白表达的检测。结果：1、高频刺激主动脉与肺动脉交界处均诱发了起源于右室流出道部位的室速,且室速持续时间均大于4小时。2、室速组L型钙通道α1c蛋白表达量明显下降;干预组L型钙通道α1cc蛋白的表达下降,但与对照组比较无显著差异。结论：1、室速组的心肌L型钙通道α1c蛋白表达发生了重构。2、维拉帕米可以改善心肌L型钙通道α1c蛋白的重构。3、L型钙通道在RVOT-VT发生、持续中起重要作用。     

Confounding factors leading to misdiagnosing ventricular tachycardia as supraventricular in the emergency room

Studies conducted during the last 50 years have proposed electrocardiographic criteria and algorithms to determine if a wide QRS tachycardia is ventricular or supraventricular in origin. Sustained ventricular tachycardia is an uncommon reason for consultation in the emergency room. The latter and the complexity of available electrocardiographic diagnostic criteria and algorithms result in frequent misdiagnoses. Good hemodynamic tolerance of tachycardia in the supine position does not exclude its ventricular origin. Although rare, ventricular tachycardia in patients with and without structural heart disease may show a QRS duration <120 ms. Interruption of tachycardia by coughing, carotid sinus massage, Valsalva maneuver, or following the infusion of adenosine or verapamil should not discard the ventricular origin of the arrhythmia. In patients with regular, uniform, sustained broad QRS tachycardia, the presence of structural heart disease or A-V dissociation strongly suggest its ventricular origin. Occasionally, ventricular tachycardia can present with AV dissociation without this being evident on the 12-lead ECG. Cardiac auscultation, examination of the jugular venous pulse, and arterial pulse palpation provide additional clues for identifying A-V dissociation during tachycardia. This paper does not review the electrocardiographic criteria for categorizing tachycardia as ventricular but rather why emergency physicians misdiagnose these patients.