Arrhythmogenic right ventricular dysplasia presenting as right ventricular outflow tract tachycardia.

A case of a 51-year old male is presented. A left bundle branch block inferior axis tachycardia was manifest. At electrophysiological study this tachycardia was inducible and was ablated in the septal right ventricular outflow tract (RVOT). Two other tachycardias were identified both with right bundle branch block (RBBB) morphology raising the suspicion of diffuse pathology. Arrythmogenic right ventricular dysplasia (ARVD) was confirmed by right ventricular angiography and magnetic resonance imaging (MRI). An implantable cardioverter defibrillator (ICD) was implanted and an appropriate shock was later delivered.     

Additional coronary sinus defibrillation lead with a right pectoral ICD and high DFT

We report the case of a 63-year-old man with ischemic cardiomyopathy having an implantable cardioverter defibrillator (ICD) implanted for repeated ventricular tachycardia (VT). After several revisions of the ICD lead, a thrombosis of the left venous system was diagnosed. A right pectoral ICD device was implanted, and a sufficient defibrillation threshold (DFT) could not be achieved during the operation. Thus, a further defibrillation lead was implanted into the coronary sinus, which successfully terminated ventricular fibrillation.     

Transluminal removal of an embolized venous catheter fragment with simple means: a case report

Vascular catheters are associated with complications like infection, thrombosis and stenosis. The embolization of a venous catheter fragment is a rare complication. This report presents a successful transluminal removal of an embolized catheter fragment in a 87-year-old patient who underwent on operative revision with renewed resection and postoperative multiorgan failure. The patient needed a large-bore catheter due to acute renal failure. By replacing the central venous catheter using the Seldinger technique a catheter fragment embolized in the right ventricle. This catheter fragment was removed with a Dormia basket.     

特发性室性心动过速的射频消融

目的对经射频消融术证实的特发性室性心动过速的病例进行总结分析,探讨室性心动过速的发病状况、心电图特点、消融靶点的确定及消融结果。方法对32例特发性室性心动过速的起源部位和体表心电图进行分析,所有患者在诱发出室性心动过速后进行射频消融治疗,观察特发性室性心动过速的射频消融成功率和复发率,以及它们和消融靶点的关系。结果右室特发性室性心动过速心电图表现为左束支传导阻滞,左室特发性室性心动过速心电图则多表现为右束支传导阻滞。消融靶点的确定右室特发性室性心动过速主要采用起搏标测法,左室特发性室性心动过速主要采用激动顺序标测法。右室流出道室速组在起搏标测起搏ECG和VT时ECG的12导联QRS波完全相同处消融成功率较高。结论室性心动过速发作时的体表心电图可初步估计特发性室性心动过速的起源部位,射频消融术治疗特发性室性心动过速成功率高、并发症少。     

Isolated noncompaction left ventricular myocardium and polymorphic ventricular tachycardia

A 57-year-old woman with syncope was admitted. She had a family history of sudden death: two brothers had died suddenly at the age of 47. Transesophageal echocardiography showed numerous prominent trabeculations and deep intertrabecular recesses in the anterior and lateroapical zones. Isotopic left ventricular ejection fraction was 46%. Cardiac catheterization showed coronary arteries with no angiographic lesions. A prominent trabecular zone and deep intertrabecular recesses were seen in the anterior wall on left ventriculography. Right ventriculography was normal. The diagnosis of isolated noncompaction left ventricular myocardium was established. Continuous 24-h electrocardiographic registry showed episodes of polymorphic ventricular tachycardia. Programmed ventricular stimulation performed at the right ventricular apex with up to three extrastimuli failed to induce ventricular arrhythmias. Treatment with beta blockers was initiated, but short runs of polymorphic ventricular tachycardia persisted. A dual-chamber automatic implantable defibrillator was implanted. We discuss the physiopathology of the arrhythmia. It appears that several factors could be responsible for the malignant arrhythmias in this entity.     

Percutaneous removal of a fractured right heart catheter from the apex of the right ventricle

A 58-year-old woman underwent right and left heart catheterization for suspected ischaemic heart disease with ventricular tachycardia. During the procedure a Bourassa catheter fractured and lodged at the right ventricular apex. Under general anaesthesia and radiographic screening the fragment was removed using a bronchoscopy biopsy forceps via the jugular vein after other methods had failed. This case highlights the need for familiarity with several techniques for the removal of such fragments.     

Catheter ablation of electrical storm in a patient with left ventricular assist device

Catheter ablation is an effective treatment for ventricular tachycardia (VT) in structural heart disease to reduce VT recurrence and implantable cardioverter defibrillator shocks.Current guidelines recommend ablation in patients with recurrent or incessant VT. In patients with left ventricular assist device (LVAD), VTs may be well tolerated hemodynamically and catheter ablation has been performed rarely, until now. We present a case of successful VT ablation in a patient with LVAD and electrical storm. Effective ablation after a transseptal LV access was achieved using electroanatomic mapping and a substrate-based approach. On the basis of this case, we discuss the pros and cons of VT ablation in these patients.     

Twister

A 75-year-old male presented with an extensive anterior myocardial infarction. He underwent primary coronary angioplasty to the proximal left anterior coronary artery, which was successful and uncomplicated. Several days later he sustained a cardiac arrest and was successfully resuscitated. An electrophysiological study revealed inducible ventricular tachycardia. An automatic implantable cardioverter defibrillator (ICD) was placed in a subcutaneous abdominal position. After the device was implanted, the patient developed pneumonia and a hematoma in the generator pocket.     

Post-myocardial infarction ventricular aneurysm and intractable ventricular tachycardia supported by left ventricular assist device: a case report

A 57-year-old man was admitted under a diagnosis of myocardial infarction. Cardiac catheterization revealed total occlusions of the right coronary artery and the left anterior descending artery, and ventriculography showed aneurysmal change in the anterior and septal segments. Circulatory support was introduced with intraaortic balloon pumping, but intractable ventricular tachycardia developed. Electrophysiological mapping and cryoablation to the myocardium were performed intraoperatively, and then coronary artery bypass grafting with endoventricular circular patch plasty of the left ventricle was carried out. Weaning from the cardiopulmonary bypass was attempted, but a left ventricular assist device was subsequently implanted to support the deteriorated ventricular function. The hemodynamics of the ventricle improved several days after the circulatory support was introduced, and the left ventricular assist device was removed successfully. This case suggests that the left ventricular assist device is an effective method to support recovery from serious complications after myocardial infarction.     

A novel treatment strategy for therapy refractory ventricular arrhythmias in the setting of arrhythmogenic right ventricular dysplasia.

Arrhythmogenic right ventricular dysplasia (ARVD) is a major cause of ventricular tachycardia and cardiac arrest in young adults. The ideal management of this genetic disorder is individual. The treatment options are antiarrhythmic drug therapy, transcatheter radiofrequency catheter ablation, implantable cardioverter defibrillator therapy, and surgical treatment [Kies P, Bootsma M, Bax J, Schalij MJ, van der Wall EE. Arrhythmogenic right ventricular dysplasia/cardiomyopathy: screening, diagnosis, and treatment. Heart Rhythm 2006;3:225-34; Verma A, Kilicaslan F, Schweikert RA et al. Short- and long-term success of substrate-based mapping and ablation of ventricular tachycardia in arrhythmogenic right ventricular dysplasia. Circulation 2005;111:3209-16]. In the following, we describe a unique case of a young patient, presenting with therapy refractory ventricular arrhythmias in the setting of ARVD, who following failed catheter ablations, has been successfully treated with beating heart cryoablation.     

Bedside programmed ventricular stimulation for sudden death risk stratification

BACKGROUND: Patients with myocardial infarction and left ventricular dysfunction are at risk for sudden death. This research was conducted to determine the applicability and safety of a bedside programmed stimulation protocol to determine the risk for sudden death in these patients. METHODS: Four hundred and twelve patients with acute myocardial infarction were studied. Left ventricular ejection fraction was evaluated by means of an echocardiogram. Ventricular arrhythmia, late potentials and heart rate variability were determined by means of Holter recordings. Fifty patients (60 +/- 14-year-old; 85% male) presented a left ventricular ejection fraction lower than 0.40 (0.36 +/- 0.10) associated with late potentials, low heart rate variability or ventricular arrhythmia greater than Lown I. After a central venous access was placed under fluoroscopy guidance and ECG monitoring, a quadripolar catheter was advanced to the right ventricular apex to perform programmed ventricular stimulation with up to three extrastimuli. The patients were followed-up to determine in-hospital morbidity and/or mortality. RESULTS: No patient suffered complications. Ventricular tachycardia or ventricular fibrillation was induced in six patients. All of them received amiodarone and in five an automatic cardioverter-defibrillator was implanted. After a 22 +/- 6 month follow-up, five patients had received appropriate discharges from the implanted device and none had suffered from arrhythmic sudden death. CONCLUSION: Bedside programmed stimulation is a safe and useful means for sudden death risk stratification in post myocardial infarction patients. It moreover presents the advantage of being cheaper than conventionally used procedures.     

Snare retrieval of a catheter fragment with inaccessible ends from the pulmonary artery

Frequent use of central venous lines has led to an increasing problem with embolized catheter fragments which have become lodged in the right heart and pulmonary vasculature. Removal of catheter fragments is justified because of a high complication rate when they are left in situ. Using a snare retrieval apparatus catheter fragments may be quickly and easily removed. In the past year we have seen 3 patients with embolized catheter fragments. One case was unusual in that its transverse position in the pulmonary vasculature required initial dislodgement with a pigtail catheter before it could be successfully snared. The literature and our experience suggest that most, if not all, catheter fragments in the right heart and pulmonary circulation can be successfully retrieved without resorting to thoracotomy.     

Malignant fascicular ventricular tachycardia degenerating into ventricular fibrillation in a patient with early repolarization syndrome

A 45-year-old man was hospitalized for syncope due to fascicular ventricular tachycardia degenerating into ventricular fibrillation (VF). The electrocardiogram showed an early repolarization syndrome. The arrhythmia was repetitive and disappeared after oral hydroquinidine. An implantable cardioverter-defibrillator (ICD) was implanted; subsequently, the patient was arrhythmia free at 9 months follow-up.     

Catheter ablation of a polymorphic ventricular tachycardia inducing monofocal premature ventricular complex

Ventricular tachycardia originating from the right ventricular outflow tract (RVOT) is considered benign, but sometimes it causes polymorphic ventricular tachycardia and ventricular fibrillation, resulting in sudden cardiac death. A 58-year-old woman without structural heart disease was admitted for evaluation of recurrent episodes of syncope. Surface ECG showed frequent repetitive premature ventricular contraction (PVC) of RVOT origin. Polymorphic ventricular tachycardia triggered by the same PVC was documented by Holter ECG during an episode of syncope. Radiofrequency catheter ablation was performed to eradicate this PVC. No polymorphic ventricular tachycardia has developed after the procedure, and the patient has had no recurrence of syncope.     

射频消融治疗室性早搏触发特发性室性心动过速／心室颤动的病例分析

目的探讨射频消融治疗在室性早搏（室早）触发特发性室性心动过速／心室颤动（室速／室颤）中的作用。方法总结3例由室早触发室速／室颤的治疗经验,1例对室早进行射频消融（RF—CA）并植入心律转复除颤器（ICD）,另1例经射频消融未完全消除室早而选择植入ICD,第3例经射频消融成功消除室早,未再发室颤。结果随访2年,3例患者均存活,ICD未再记录到室速／室颤。结论在室早触发室速／室颤病例中,应分析室早与室速／室颤的相关性,给予个体化治疗,射频消融室早可以消除／减少晕厥和室颤的发作。     

A case of arrhythmogenic right ventricular cardiomyopathy

The present report describes a 40-year-old woman with a long history of monomorphic ventricular tachycardia and left bundle branch block. She was treated with various antiarrhythmic agents; ventricular tachycardia ablation was attempted and an automatic implantable cardioverter defibrillator was implanted. Three-dimensional echocardiography clearly demonstrated features of arrhythmogenic right ventricular cardiomyopathy, including marked right ventricular (RV) dilation, decreased RV systolic function and thinning of the RV free wall. Other RV morphological abnormalities included excessive trabeculations and a localized apical aneurysm. Two years later, the patient developed symptoms of congestive heart failure. Despite maximal medical therapy, her clinical condition continued to deteriorate and she was referred for heart transplantation. Results of the pathology of her explanted heart confirmed this rare diagnosis. She presented with an unusual clinical course for arrhythmogenic right ventricular cardiomyopathy, which was complicated by progressive congestive heart failure and ultimately required heart transplantation. Three-dimensional echocardiography identified the structural abnormalities related to this rare disease.     

Radiofrequency catheter ablation of ventricular tachycardia in patients with an implantable defibrillator. Long-term follow-up

INTRODUCTION AND OBJECTIVES: The frequent occurrence of ventricular tachycardia can be a serious problem for patients with an implantable defibrillator, and may necessitate adjuvant antiarrhythmic therapy or radiofrequency catheter ablation. We analyzed the long-term results obtained with this latter therapy in patients suffering from frequent or continuous ventricular tachycardia. PATIENTS AND METHOD: Eighteen ablation procedures were performed in 11 patients who had a defibrillator implanted because of previous syncopal ventricular tachycardia. All were men, aged 67.64 (5.87) years; 10 patients had had a myocardial infarction 15.50 (5.08) years earlier, and one suffered from arrhythmogenic right ventricular dysplasia. RESULTS: Electrophysiologically, treatment was initially successful in 8 patients (72.73%). After a follow-up period of 39.10 (24.70) months, the number of defibrillator discharges decreased significantly in all patients, from 52.82 (35.73) to 0.64 (1.03) (P=.001). During follow-up, ventricular tachycardia occurred in nine patients. In five, it took the same form as the ablated ventricular tachycardia. Six patients needed additional ablation procedures: two because of initial failure, three because of recurrence, and one because a different ventricular tachycardia occurred. In addition to the good electrophysiological results obtained, long-term clinical evolution was favorable in all patients. CONCLUSIONS: Radiofrequency ablation successfully disrupts frequent or continuous ventricular tachycardias and significantly reduces the defibrillator discharge rate even when ablation has failed electrophysiologically. It is particularly useful in these latter critical situations, in which other therapies are not sufficiently effective. Because our patients mainly had ischemic heart disease and were highly susceptible to new arrhythmias during follow-up, ablation complemented rather than replaced the implantable defibrillator.     

Long-term outcome of pharmacological and nonpharmacological treatment for ventricular arrhythmias

Recent advances of nonpharmacological therapy such as catheter ablation and implantable cardioverter defibrillator and lessons from the Cardiac Arrhythmia Suppression Trial(CAST) have changed the strategy for ventricular arrhythmias. The safety and efficacy of radiofrequency catheter ablation of symptomatic sustained monomorphic ventricular tachycardia without structural heart disease has made ablation the firstline curative therapy. In idiopathic ventricular fibrillation such as Brugada syndrome, an implantable cardioverter defibrillator is the most effective treatment to prevent sudden cardiac death. In patients with asymptomatic ventricular tachyarrhythmias in heart failure, class I antiarrhythmic drugs should be avoided due to proarrhythmic and negative inotropic effects that may be responsible for increased mortality in some trials. In such patients, amiodarone and beta-blocker may reduce sudden cardiac death. For patients with sustained ventricular tachycardia or ventricular fibrillation in heart failure, amiodarone or implantable cardioverter defibrillator should be considered. In comparison with amiodarone, implantable cardioverter defibrillator markedly reduced sudden death in ventricular tachycardia and ventricular fibrillation survivors in Antiarrhythmics Versus Implantable Defibriltors(AVID). Although better patient selection and clarification of mapping criteria improved the successful ablation rate in patients with structural heart disease, candidates of ablation are few. In patients with extensive structural heart disease, multiple ventricular tachycardias are often present. Catheter ablation of a single ventricular tachycardia may be only palliative. Therefore, implantable cardioverter defibrillator is the most effective treatment to prevent sudden cardiac death, with amiodarone and ablation as the adjunctive therapy to prevent frequent ventricular tachycardia. Furthermore, an implantable cardioverter defibrillator improved survival in selected patients with depressed ventricular function after myocardial infarction, who also have nonsustained and inducible sustained ventricular tachycardia in Multicenter Automatic Defibrillator Implantation Trial(MADIT) and Multicenter Unsustained Tachycardia Trial(MUSTT).     

AV reentrant and idiopathic ventricular double tachycardias: complicated interactions between two tachycardias

An electrophysiological study was performed in a 61 year old man with Wolff- Parkinson-White (WPW) syndrome. At baseline, neither ventricular nor supraventricular tachycardias could be induced. During isoprenaline infusion, ventricular tachycardia originating from the right ventricular outflow tract (RVOT) with a cycle length of 280 ms was induced and subsequently atrioventricular reentrant tachycardia (AVRT) with a cycle length of 300 ms using an accessory pathway in the left free wall appeared. During these tachycardias, AVRT was entrained by ventricular tachycardia. The earliest ventricular activation site during the ventricular tachycardia was determined to be the RVOT site and a radiofrequency current at 30 W successfully ablated the ventricular tachycardia at this site. The left free wall accessory pathway was also successfully ablated during right ventricular pacing. The coexistence of WPW syndrome and cathecolamine sensitive ventricular tachycardia originating from the RVOT has rarely been reported. Furthermore, the tachycardias were triggered by previous tachycardias.     

Clinical efficacy of dual electrode systems for endocardial cardioversion of ventricular tachycardia: a prospective randomized crossover trial

In order to eliminate the need for epicardial electrodes, two large transvenous catheter electrodes or one catheter and one extrathoracic patch electrode have been proposed as alternative electrode configurations for defibrillation and ventricular tachycardia cardioversion by implantable cardioverter/defibrillators. We compared the efficacy and safety of endocardial shocks delivered through these two electrode systems in man in a prospective randomized crossover study. Twelve patients with sustained ventricular tachycardia and heart disease undergoing electrophysiologic study were evaluated. A transvenous tripolar cardioversion electrode catheter with a large distal defibrillation electrode (surface area, 400 mm2) and proximal defibrillation electrode (surface area, 800 mm2) was positioned in the right ventricular apex with a cutaneous patch electrode placed on the cardiac apex. Sustained ventricular tachycardia was induced at electrophysiologic study. Shocks were delivered using two catheter electrodes only (right ventricular cathode and right atrial anode = method I), and one catheter electrode and cutaneous patch (right ventricular cathode and cutaneous apical patch anode = method II). Synchronized monophasic shocks were delivered using three preselected protocols based on ventricular tachycardia cycle length and morphology. Initial shock energies were 25 joules for polymorphic ventricular tachycardia and ventricular fibrillation, 15 joules for monomorphic rapid ventricular tachycardia (cycle length less than or equal to 300 msec), and 5 joules for monomorphic slow ventricular tachycardia (cycle length greater than 300 msec). Ventricular tachycardia was reinduced and shock energies titrated until cardioversion threshold was obtained. Identical ventricular tachycardia episodes were treated with both methods at each energy level.(ABSTRACT TRUNCATED AT 250 WORDS)