Ablation Of Idiopathic Ventricular Tachycardia Research Articles

Low power ablation for left coronary cusp ventricular tachycardia—Efficacy and long-term outcome

BackgroundThe left coronary cusp is an uncommon but well-known site for the ablation of idiopathic ventricular tachycardia (VT). Proximity to the left coronary ostium makes ablation of this arrhythmia challenging. Different power settings have been described by various operators. Our objective was to describe the outcomes with low power ablation. MethodsOnce mapping confirmed origin from the left coronary cusp, ablation was performed if the best site was situated at least 5 mm from the left coronary ostium. Ablation was started at 15 W and, if successful, was stopped after 30 s. When required, higher powers were used up to 30 W. ResultsTen patients with VT or premature ventricular beats mapped to the left coronary cusp were included in the study. No ablation was performed in one patient because of proximity to the left coronary ostium. Successful ablation was performed in eight of the other nine patients with a mean power of 18.1 ± 5.3 W and duration of 42.2 ± 13.5 s. There were no complications. All the eight patients remained free of recurrence at 16.8 ± 16.5 months of follow-up. ConclusionsVT can be ablated from the left coronary cusp close to the left coronary ostium. Ablation with low power is effective in achieving immediate success which is also durable with time while avoiding complications.

P812Clinical validation of automatic local activation time annotation during idiopathic ventricular tachycardia ablation procedures

P812Clinical validation of automatic local activation time annotation during idiopathic ventricular tachycardia ablation procedures

1154Clinical validation of automatic local activation time annotation during idiopathic ventricular tachycardia ablation procedures

1154Clinical validation of automatic local activation time annotation during idiopathic ventricular tachycardia ablation procedures

Successful ablation of incessant idiopathic right ventricular tachycardia arising from unusual sites in children

Most idiopathic right ventricular tachycardias originate from the outflow tract. We present a case series of idiopathic incessant ventricular tachycardia arising from unusual sites of the right ventricle in children, which were well resolved by catheter ablation. A retrospective review was performed of all three patients who underwent ablation of idiopathic ventricular tachycardia below the level of the right ventricular outflow tract using three-dimensional mapping in our institute. Result All three patients presented with tachycardia-induced cardiomyopathy due to incessant ventricular tachycardia on first admission. The sites of successful ablation were at the proximal right bundle branch, distal right bundle branch, and apex of the right ventricle, respectively. No complications occurred, and there has been no recurrence of ventricular tachycardia after the final ablation at an average follow-up period of 9 months. All three patients have achieved normalisation of left ventricular size and systolic function. Incessant idiopathic ventricular tachycardia originating from unusual sites of the right ventricle in children, resulting in significant symptoms and impaired ventricular function, can be successfully treated with catheter ablation.

Catheter ablation of idiopathic ventricular tachycardia without the use of fluoroscopy

BackgroundCatheter ablation is the treatment of choice for many patients with idiopathic ventricular tachycardia (VT). Unfortunately, conventional catheter ablation is guided by fluoroscopy, which is associated with a small but definite radiation risk for patients and laboratory personnel. The aim of our study is to assess feasibility, success rate and safety of idiopathic VT ablation procedure performed without the use of fluoroscopy. MethodsNineteen consecutive patients undergoing idiopathic VT ablation at our institution have been included. The ablation procedures were performed under the guidance of electroanatomical mapping (EAM) system and intracardiac echocardiography (ICE). ResultsNineteen patients (mean age 38.7years) underwent ablation procedure for idiopathic VT. Twelve (63%) had outflow tract VT, 3 (18%) fascicular tachycardia, 2 (11%) peri-tricuspidal VT, 1 (5%) peri-mitral VT, and 1 (5%) lateral left free-wall VT. The mean procedural time was 170.2±45.7min. No fluoroscopy was used in any procedural phase. Acute success rate was 100%. No complication was documented in any patients. After a mean follow up of 18±4months, recurrences occurred in 2 patients. ConclusionsIn our preliminary experience idiopathic VT ablation without the use of fluoroscopy was feasible and safe, using a combination of EAM and ICE. Success rate was excellent with no complication.

Safety and efficacy of three-dimensional mapping systems in idiopathic ventricular tachycardia ablation

Background: Idiopathic ventricular tachycardia (VT) accounts for approximately 10% of all patients referred for evaluation of VT. 3-D mapping system has proved very useful in ablation of complex arrhythmias e.g. atrial fibrillation and VT in structural heart disease. The aim of the current study is to evaluate safety and efficacy of new 3-D mapping system in idiopathic VT ablation and comparison of between contact (Carto™) and noncontact (EnSite Array™ Catheter) mapping systems. Materials and Methods: Study population included 62 patients with idiopathic VT. (27 female 35 male, mean age 43.5 ± 22.4 years). Six patients had previously undergone unsuccessful ablation in other centers using conventional method. Site of VT/PVCs origin was RVOT in 44 (70.9%), LVOT in 4 (6.5%) and LV cavity 14 (22.6%) patients. VT was successfully ablated in 54/62 (87.1%) patients and ablation was not successful in 8/62 (12.9%) patients. VT was successfully ablated in all (6/6) patients who had previous failed ablation with conventional methods. Four (6.4%) patients developed procedure related complications. No patient with successful ablation had recurrence at six months follow up and 6/8 patients in whom ablation failed had recurrence during follow up. There was no difference in safety and efficacy of two mapping systems (success rate was 90.9% in EnSite and 82.5% in Carto (p 0.6)). Conclusion: New 3-D mapping systems (Carto™, EnSite Array™ Catheter) are very useful in ablation of idiopathic VTs with good acute success and short-term follow up. These systems are particularly useful in patients with failed ablation by conventional methods. There is no difference the two systems with regards to acute success, recurrence and complications rate.

Radio frequency ablation for VT – A cost-effective tool to combat SCD in developing countries

Radio frequency ablation for VT – A cost-effective tool to combat SCD in developing countries

Catheter ablation of idiopathic ventricular tachycardia in children using the EnSite NavX system with/without fluoroscopy

Curative therapy of idiopathic ventricular tachycardia remains a challenge in interventional electrophysiology. The aim of this study was to demonstrate the utility of an EnSite NavX system in the catheter ablation of idiopathic ventricular tachycardia in children. In all, 17 children with idiopathic ventricular tachycardia underwent electrophysiological studies using the EnSite NavX system guidance. The mean patient age was 13 ± 2.4 years (range: 7.8-17.9) and the mean patient weight was 52.3 ± 11.9 kg (range: 32-75). The origin of ventricular tachycardia was in the right ventricular outflow tract in nine patients, in the left ventricle in six, near the bundle of His/right bundle branch in one, and in the left aortic cusp in one. The mean procedure and fluoroscopy times were 169.3 ± 43.2 minutes and 8 ± 10.8 minutes, respectively. No fluoroscopy was used in six patients. The mean radiation exposure was 33.1 ± 56.4 mGy. Acute success was achieved in 14 patients (82%). The focus of ventricular tachycardia was epicardial in two failed procedures. During a mean follow-up of 8.5 ± 7.6 months, ventricular tachycardia recurred in three patients, two of whom underwent a second procedure. Except for one patient who developed transient right bundle branch block, no complications were seen. Catheter ablation of idiopathic ventricular tachycardia in children can be performed safely and effectively with low fluoroscopy exposure using the EnSite NavX system.

Radiofrequency catheter ablation of idiopathic ventricular tachycardia originating from the mitral annulus

Idiopathic ventricular tachycardias (VT) originate mostly from the right ventricular outflow tract and rarely from the mitral annulus. Herein, we present a 20-year-old male patient in whom we performed a successful radiofrequency catheter ablation of mitral annular VT. He admitted to our department with the complaints of palpitations and shortness of breath attacks for 5 years. Detailed assessment disclosed idiopathic VT which subsequently was found to be derived from the mitral annulus in electrophysiologic study. The patient's symptoms disappeared after successful RF ablation and the follow-up Holter ECG was totally normal.

Radiofrequency catheter ablation of idiopathic ventricular tachycardia originating from mitral annulus

Radiofrequency catheter ablation of idiopathic ventricular tachycardia originating from mitral annulus

Catheter Ablation of Idiopathic Ventricular Tachycardia Originating from Myocardial Extensions into a Noncoronary Aortic Cusp

We present a 34-year-old woman with idiopathic ventricular tachycardia that resisted 2 previous attempts for catheter ablation and was successfully ablated in the myocardial extension within the noncoronary aortic cusp.

Catheter ablation of idiopathic left and right ventricular tachycardias in the pediatric population using noncontact mapping

Idiopathic ventricular tachycardia (VT) in children with a structurally normal heart can cause significant morbidity, and although rare, mortality. Conventional activation and pace mapping may be limited by nonsustained tachycardia or unstable hemodynamics. The aim of this study was to assess feasibility of catheter ablation of idiopathic VT in the pediatric population guided by noncontact mapping. Twenty consecutive pediatric patients with idiopathic VT underwent electrophysiologic study with the intention to use the noncontact mapping system EnSite 3000 (EnSite Array, St. Jude Medical Inc., Minneapolis, Minnesota). The multielectrode balloon array was introduced into the left or right ventricle, respectively, and tachycardia was analyzed using color-coded isopotential maps as well as reconstructed unipolar electrograms on the virtual geometry. The region of origin was identified in all of them, and the site of earliest activation with a QS pattern of the unipolar electrograms was guided for sites of ablation. Idiopathic VT originated from the right ventricular outflow tract in 6 patients, from the left ventricle in 8, and from the aortic sinus cusp in 6 in this cohort with a median age of 14.4 (range: 4.8 to 20.9) years. Ablation was attempted in 18 of 20 children, and was acutely successful in 17 of these 18 (94%). During a mean follow-up of 2.3 +/- 1.7 years, VT recurred in 3, 2 of them have been treated with a second procedure, resulting in an overall intermediate-term success in 16 of 18 (89%) children with idiopathic VT. Noncontact mapping can safely and effectively be used to map and guide catheter ablation of the tachycardia substrate of idiopathic VT in pediatric patients.

Catheter‐Based Cryoablation of Postinfarction and Idiopathic Ventricular Tachycardia: Initial Experience in a Selected Population

Transvenous cryoablation has proven to be safe and effective for the treatment of supraventricular arrhythmias. The aim of this prospective study was to report the feasibility and safety of catheter-based cryoablation for the treatment of postinfarction and idiopathic ventricular tachycardia (VT). Catheter-based cryoablation was performed in 17 patients (15 men, 58 +/- 18 years). VT occurred after a prior myocardial infarction in 10 and was idiopathic in 7 patients. Cryoablation was performed with a 10-F, 6.5-mm tipped catheter. The ablation site was selected using entrainment mapping techniques for postinfarction VT. The site of the earliest activation time with optimal pace mapping was used for ablation of idiopathic VT. All targeted VTs (12 postinfarction and 7 idiopathic) were acute successfully ablated after a median number of 2 applications of 5 minutes with an average temperature of -82 +/- 4 degrees C. Mean procedure and fluoroscopy times were 204 +/- 52 and 52 +/- 20 minutes for postinfarction VT and 203 +/- 24 and 38 +/- 15 minutes for idiopathic VT. No cryocatheter or cryoenergy complications were observed. After a follow-up of 6 months, 4 of the 10 patients with postinfarction VT had a recurrence. In 1 of the 7 patients with idiopathic VT the index arrhythmia recurred. In this small patient population, catheter-based cryoablation of VT was safe and effective. Future studies are needed to evaluate the effect of cryothermy in a larger group of patients, especially those with postinfarction VT.

Catheter Ablation of Idiopathic Ventricular Tachycardia Arising from the Aortic Root

Most idiopathic ventricular tachycardia (VT) arises from the area of the outflow tracts, and the most common left ventricular site is the aortic root, usually from the right and left sinuses of Valsalva. This site of origin is suggested by specific patterns on the electrocardiogram. Activation mapping and pace mapping are both useful strategies, and their relative benefits and limitations need to be appreciated. The mapping strategy for a VT of suspected aortic root origin is based on the consideration that multiple chambers may need to be mapped, and the temptation to ablate at suboptimal sites based on the justification that it was easy to get to should be resisted. The entire surface of each cusp needs to be sampled, as distinct activation times and pacemaps are obtained at each site. Standard radiofrequency energy is typically adequate and the precision of mapping rather than the amount of tissue ablated is tantamount to success. In my opinion, the indications for ablation of aortic root VT are similar to those for other idiopathic VT. Although I offer patients both pharmacologic and nonpharmacologic options, I feel that ablation is first line therapy for patients with sufficient symptoms to warrant therapy.

Radiofrequency catheter ablation of idiopathic ventricular tachycardia and symptomatic premature ventricular contraction originating from valve annulus

Radiofrequency catheter ablation (RFCA) has been established as an effective and curative therapy for ventricular tachycardia (VT) and severely symptomatic premature ventricular contraction (PVC) from the outflow tract in structurally normal hearts. This study aimed to investigate electrophysiologic characteristics and effects of RFCA for patients with idiopathic VT and symptomatic PVC originating from the valve annulus. Characteristics of body surface electrocardiogram (ECG) and endocardiogram in a successful RFCA target were analyzed in 16 patients with idiopathic VT and symptomatic PVC originating from the valve annulus. Additionally, the ECG characteristics of VT or PVC were compared with those of manifest Wolff-Parkinson-White (WPW) syndrome originating from the same site of origin in 15 patients. Thirteen patients were successful, 2 recurrent and 1 failed. The recurrent cases underwent successful ablation the second time guided by the Ensite 3000 mapping system. In all patients with the WPW syndrome, the characteristics of QRS morphology were well matched with those of the VT and PVC that originated from corresponding sites of origin. RFCA is an effective curative therapy for VT and symptomatic PVC originating from the valve annulus. There are specific characteristics in ECG and the ablation site could be located by means of the WPW syndrome accessory pathway's algorithm.

Twelve-lead electrocardiographic characteristics of the aortic cusp region guided by intracardiac echocardiography and electroanatomic mapping

The most common site of origin of idiopathic ventricular tachycardia (VT) is the right ventricular outflow tract. Idiopathic VT also can arise from the left ventricular outflow tract and the surrounding structures. Morphologic descriptions of 12-lead ECG characteristics of the aortic cusp region are limited. The purpose of this study was to define unique ECG characteristics of the aortic cusp region by performing a systematic analysis of pacemapping of this region in patients with structurally normal hearts. A combination of electroanatomic mapping, intracardiac echocardiography, and fluoroscopic guidance was used to study a total of 30 patients with structurally normal hearts undergoing left-sided ablation procedures. Each of the aortic valve cusps and the aortomitral continuity were paced at threshold and analyzed offline to determine unique ECG characteristics. Pacing from the left coronary cusp typically produced a multiphasic QRS morphology consistent with an M or W pattern in lead V(1) with a precordial transition (R>S) no later than V(2). Pacing from the right coronary cusp typically resulted in a left bundle-type pattern with a broad small R wave in V(2) and a precordial transition generally at V(3). Pacing from the aortomitral continuity resulted in a qR pattern that was not observed anywhere else in the left ventricular outflow tract. When comparing the right coronary cusp and left coronary cusp, the precordial transition was earlier in the left coronary cusp than in the right coronary cusp. Pacing the noncoronary cusp uniformly resulted in atrial capture. When considering ablation of idiopathic VT, the aortic cusps and aortomitral continuity must be considered as possible foci. The 12-lead ECG, a readily and easily obtainable source of information, has useful characteristics for differentiating VTs arising from the cusp region.

Catheter Ablation for Ventricular Tachycardia

Sustained ventricular tachycardia (VT) is an important cause of morbidity and sudden death in patients with heart disease.1 Implantable cardioverter-defibrillators (ICDs) terminate VT episodes, reducing the risk of sudden death. Recurrent VT develops in 40% to 60% of patients who receive an ICD after an episode of spontaneous sustained VT. A first episode of VT occurs in ≈20% of patients within 3 to 5 years after ICD implantation for primary prevention of sudden death in high-risk groups.2–4 ICD shocks reduce quality of life and are associated with an increased risk of death.2–4 Antiarrhythmic drug therapy with amiodarone or sotalol reduces VT episodes but with disappointing incidence of side effects and efficacy.2 Catheter ablation is useful for reducing VT episodes and can be life-saving when VT is incessant.1,5,6 Idiopathic VTs occur in patients without structural heart disease and rarely cause sudden death. Electrophysiological study with catheter ablation is often warranted to confirm the diagnosis, to provide further evidence for the absence of ventricular scar or other disease, and often to cure the arrhythmia. Ablation is also an option for symptomatic nonsustained VT and frequent ventricular ectopy in these patients.1 The appearance of the VT on ECG often suggests its likely cause and associated heart disease (Figure 1). Monomorphic VT has the same QRS complex from beat to beat, indicating repetitive ventricular activation from a structural substrate or focus that can be targeted for ablation. Most are due to reentry through regions of ventricular scar.7 Figure 1. ECG types of VT and most common causes are shown with characteristic ECG features of selected VTs. LBBB indicates left bundle-branch block; LVOT, LV outflow tract; RBBB, right bundle-branch block; L, left; and R, right. Polymorphic VTs have a changing ventricular activation sequence that can be due to …

Ablation of Idiopathic Ventricular Tachycardia in Two Separate Regions of the Outflow Tract: Prevalence and Electrocardiographic Characteristics

Few studies have clarified the prevalence and characteristics of idiopathic outflow tachycardia (OT-VT) with an altered QRS morphology after radiofrequency catheter ablation (RFCA), requiring additional RFCA applications at a different portion of the outflow tract (OT) to abolish the OT-VT. Among 344 patients (97 VTs and 247 premature ventricular contractions), 12 (3.5%; VTs-7, PVCs-5; 6 women) had dynamic QRS morphology changes following the RFCA, requiring additional RFCA applications at a different portion to abolish the OT-VT. In 8 of 12 patients (67%), this phenomenon occurred following RFCA at right (RVOT; n = 7) or left ventricular (LVOT; n = 1) endocardial sites of the OT: The second OT-VT was consistently associated with an increase in the R-wave amplitude in the inferior leads, and in five it was finally abolished by RFCA at the left sinus of Valsalva (LSV). Conversely, in four patients (33%), the second OT-VT appeared after RFCA at the LSV: two required additional RFCA applications at the LVOT to abolish the second OT-VT, and one at the RVOT, and all were associated with a decrease in the R-wave amplitude in the inferior leads. This kind of dynamic QRS morphology change was often observed when RFCA was applied to either the first or second OT-VT at a right or left ventricular endocardial site, with the other site being the LSV. A detailed continuous observation of the QRS morphology, especially of the R-wave in the inferior leads, is important for identifying changes in the QRS morphology during RFCA.

Ablation of Idiopathic Ventricular Tachycardia with a Left Bundle-Branch Block Morphology Originating from the Pulmonary Artery

We successfully performed radiofrequency catheter ablation (RFCA) in 2 cases involving patients with idiopathic ventricular tachycardias (VTs) and premature ventricular contractions (PVCs) originating from the pulmonary artery (PA). The QRS morphology of the VTs and PVCs in the two cases exhibited a left bundle-branch block (LBBB) morphology with an inferior axis. Activation and pace mappings were performed in the right ventricular outflow tract (RVOT) and above the pulmonary valve to determine the origin of the VTs and PVCs. In both cases, the earliest ventricular activation was recorded in the PA above the pulmonary valve. Applications of radiofrequency current at those sites in the PA resulted in the elimination and noninducibility of the VT and PVC. During the follow-up, the VT or PVC did not recur without any antiarrhythmic drug administration.

Idiopathic ventricular tachycardia originating in the great cardiac vein

A 44-year-old woman with no structural heart disease and a history of recurrent wide complex tachycardia was referred for radiofrequency (RF) ablation of idiopathic ventricular tachycardia (VT). Electrophysiologic study demonstrated normal sinus rhythm with frequent premature ventricular beats, a left bundle branch block morphology, and inferior axis identical to the previously documented tachycardia. Sustained VT of the same morphology was easily induced with ventricular burst pacing during isoproterenol infusion at 2 μg/min (Figure 1A).