Radiofrequency Catheter Ablation For Treatment Research Articles

Long-Term Clinical Outcome of Radiofrequency Catheter Ablation for Treatment of Bundle Branch Re-Entrant Ventricular Tachycardia

Long-Term Clinical Outcome of Radiofrequency Catheter Ablation for Treatment of Bundle Branch Re-Entrant Ventricular Tachycardia

Electrophysiological Characteristics and Radiofrequency Catheter Ablation Treatment of Idiopathic Ventricular Arrhythmias Successfully Ablated From the Ostium of the Coronary Sinus.

Idiopathic ventricular arrhythmias (VAs) rarely arise from the epicardium at the crux of the heart. However, the electrophysiological characteristics of VAs successfully ablated from the ostium of the coronary sinus (CSO) have not yet been documented.Methods and Results:Electrocardiographic and electrophysiological data were analyzed in patients with idiopathic VAs successfully ablated from the CSO.Among 309 patients with idiopathic VAs treated with radiofrequency catheter ablation (RFCA), 6 (1.94%; 3 men; age: 66.3±9.7 years) had VAs successfully ablated from the CSO. Only 1 patient had sustained ventricular tachycardia. The morphology of the QRS showed a left superior axis and QS pattern in leads III and aVF. Furthermore, the precordial maximum deflection index was >0.55 in all patients and a right bundle branch block pattern was recorded in 5 of 6 patients. All VAs were successfully eliminated by RFCA within the CSO. Intracardiac ECGs at sites where VAs were eliminated by RFCA showed clear atrial and ventricular potentials (atrial amplitude: 0.21±0.11 mV; ventricular amplitude: 0.43±0.24 mV), except in 1 case of atrial fibrillation. No patients had recurrence during the 3.4±1.8-year follow-up period. The idiopathic VAs in our study were eliminated by RFCA within the CS, where a clear atrial amplitude was recorded.

Simulated imaging of atherosclerotic & radiofrequency ablation lesions using phase subtraction.

Cardiovascular diseases are the main cause of death worldwide. Atherosclerosis and atrial fibrillation are structural and electrical pathophysiology, respectively, that can lead to acute events such as stroke or myocardial infarction. We used particle-based Monte Carlo methods to simulate X-ray phase imaging of atherosclerotic plaque types IV-VIII in the aorta, iliac, and coronary arteries. We also assessed scar lesion development in radiofrequency catheter ablation treatment of atrial fibrillation by simulating lesions 2, 5, 10, 30, and 60 days post-procedure. For both applications, we found high signal-to-noise and contrast-to-noise ratios in all lesions. These results suggest that X-ray phase imaging is a viable technique for non-invasive quantitative cardiovascular lesion characterization.

Effect of radiofrequency catheter ablation on function and structure of left ventricle during treatment for frequent premature ventricular beats

Objective To investigate the effect of radiofrequency catheter ablation(RFCA) on the function and structure of left ventricle during treatment for frequent premature ventricular beats(PVBs).Methods Totally 56 patients with PVBs,who had been successfully treated with RFCA from Jan.2006 to Dec.2010,were included in the present study(ablation group).The other 42 patients with frequent PVBs,who received no RFCA treatment,served as controls(non-ablation group).The changes of total number of PVBs,left ventricular ejection fraction(LVEF),left ventricular end-diastolic diameter(LVEDD),left ventricular end-systolic diameter(LVESD),interventricular septal diameter(IVSd),left ventricular posterior wall diameter(LVPWd) were observed before and after different treatments.Results(1)Compared with the non-ablation group,the ablation group had significantly reduced total number of PVBs([125±113]/24 h vs [17 813±1 542]/24 h,P0.01),increased LVEF([0.72±0.06] vs [0.64±0.08],P0.05),and significantly decreased LVEDD([44.1±4.0] mm vs [48.9±3.8] mm),LVESD([27.0±3.7] mm vs [30.1±4.2] mm),IVSd([7.5±0.8] mm vs [8.5±0.8] mm),and LVPWd([7.5±0.8] mm vs [8.5±0.9] mm)(P0.05).(2)Compared with the baseline levels,the total number of PVBs in the ablation group decreased from(23 662±12 559)/24 h before RFCA to(125±113)/24 h(P0.01) after RFCA,and patients had relieved chest tightness and heart palpitations.Meanwhile,the LVEF was significantly increased after RFCA([0.72±0.06] vs [0.64±0.09],P0.05);LVEDD([44.1±4.0] mm vs [50.6±5.4] mm),LVESD([27.0±3.7] mm vs [32.1±5.3] mm),IVSd([7.5±0.8] mm vs [8.8±1.1] mm),and LVPWd([7.5±0.8] mm vs [8.7±1.1] mm) were significantly decreased after RCFA(P0.05).Conclusion RFCA can effectively improve the structural remodeling and cardiac dysfunction induced by PVBs,relieving the patient symptoms.

Papillary Muscle Ventricular Tachycardia: Another Zigsaw Puzzle to Be Solved

Papillary Muscle Ventricular Tachycardia: Another Zigsaw Puzzle to Be Solved

Radiofrequency Catheter Ablation in Children with Supraventricular Tachycardias: Intermediate Term Follow up Results

The Purpose of the StudyRadiofrequency (RF) catheter ablation represents an important advance in the management of children with cardiac arrhythmias and has rapidly become the standard and effective line of therapy for supraventricular tachycardias (SVTs) in pediatrics. The purpose of this study was to evaluate the intermediate term follow up results of radiofrequency catheter ablation in treatment of SVT in pediatric age group.MethodsA total of 60 pediatric patients (mean age = 12.4 ± 5.3 years, ranged from 3 years to 18 years; male: female = 37:23; mean body weight was 32.02 ± 12.3 kg, ranged from 14 kg to 60 kg) with clinically documented SVT underwent an electrophysiologic study (EPS) and RF catheter ablation at Children’s Hospital Mansoura University, Mansoura, Egypt during the period from January 2008 to December 2009 and they were followed up until October 2011.ResultsThe arrhythmias included atrioventricular reentrant tachycardia (AVRT; n = 45, 75%), atrioventricular nodal reentrant tachycardia (AVNRT; n = 6, 10%), and atrial tachycardia (AT; n = 9, 15%). The success rate of the RF catheter ablation was 93.3% for AVRT, 66.7% for AVNRT, and 77.8% for AT, respectively. Procedure-related complications were infrequent (7/60, 11.7%), (atrial flutter during RF catheter ablation (4/60, 6.6%); ventricular fibrillation during RF catheter ablation (1/60, 1.6%); transient complete heart block during RF catheter ablation (2/60, 3.3%)). The recurrence rate was 8.3% (5/60) during a follow-up period of 34 ± 12 months.ConclusionRF catheter ablation is an effective and safe method to manage children with SVT.

A study on the opportunity for paroxysmal supraventricular tachycardia treatment with radiofrequency catheter ablation: an insight from older patients with paroxysmal supraventricular tachycardia

BackgroundAlthough Radiofrequency catheter ablation (RFCA) treatment for patients with paroxysmal supraventricular tachycardia (PSVT) has been proven to be an effective therapy, many patients, especially the older people, often refuse to...

Clinical Course of Arrhythmogenic Right Ventricular Cardiomyopathy in the Era of Implantable Cardioverter-Defibrillators and Radiofrequency Catheter Ablation

This study investigated the clinical course of arrhythmogenic right ventricular cardiomyopathy (ARVC) patients and in particular evaluated the contribution of radiofrequency catheter ablation (RFCA) and an implantable cardioverter-defibrillator (ICD) to the treatment of ARVC. ARVC is a myocardial disorder and a cause of sudden cardiac death due to ventricular tachycardia (VT). Little is known about its prognosis in Japanese ARVC patients. Thirty-five ARVC patients were studied. Mean age of patients whose onset of ARVC was congestive heart failure (CHF) (66.0 +/- 4.0 years) was significantly higher than those whose onset was VT (44.5 +/- 14.8 years, P < 0.05). ARVC patients with CHF onset showed significantly higher death rates compared to those with VT onset. ICD treatment significantly reduced episodes of hospitalization due to VT (0.1 +/- 0.4 episodes) in comparison to treatment by RFCA (1.7 +/- 2.2 episodes, P < 0.03). RFCA treatment did not reduce recurrence of VT in the follow-up period. ICD therapy showed comparable mortality to RFCA treatment. The prognosis of ARVC with CHF onset is poor. ICD therapy significantly reduced hospitalization due to VT compared with RFCA treatment. ICD implantation in combination with medication may be a better treatment for ARVC.

Cost-Effectiveness Of Catheter Ablation Treatment For Patients With Symptomatic Atrial Fibrillation.

Background: Atrial Fibrillation is the most common cardiac arrhythmia. It increases the risk of thromboembolic events and many atrial fibrillation patients suffer quality of life impairment due to disturbed heart rhythm. Pulmonary vein isolation using radiofrequency catheter ablation treatment is aimed at maintaining sinus rhythm ultimately improving quality of life. Randomized clinical trial have shown that catheter ablation is more effective than antiarrhythmic drugs for the treatment of atrial fibrillation, but its impact on quality of life and cost-effectiveness has not been widely studied. Aims: To assess the cost-effectiveness of radiofrequency ablation (RFA) vs. antiarrhythmic drug (AAD) treatment, among symptomatic atrial fibrillation patients not previously responding to AAD. Methods: A decision-analytic Markov model was developed to assess costs and health outcomes in terms of quality adjusted life years (QALYs) of RFA and AAD over a lifetime time horizon. We conducted a literature search and used data from several sources as input variables of the model. One-year rates of atrial fibrillation with RFA and AAD, respe tively, were available from published randomized clinical trials. Other data sources were published papers and register data. Results: The RFA treatment strategy was associated with reduced costs and an incremental gain in QALYs compared to the AAD treatment strategy. The results were sensitive to whether long-term quality of life improvement is maintained for the RFA treatment strategy and the risk of stroke in the different atrial fibrillation health states. Conclusion: This study shows that the short-term improvement in atrial fibrillation associated with RFA is likely to lead to long-term quality of life improvement and lower costs indicating that RFA is cost-effective compared to AAD.

Radiofrequency catheter ablation in treatment of idiopathic ventricular arrhythmia originating from left ventricular outflow tract:our experience

Radiofrequency catheter ablation in treatment of idiopathic ventricular arrhythmia originating from left ventricular outflow tract:our experience

Safety and efficacy of cryothermal and radiofrequency catheter ablation in treatment of typical atrial flutter

Safety and efficacy of cryothermal and radiofrequency catheter ablation in treatment of typical atrial flutter

Efficacy of Radiofrequency Catheter Ablation in Treatment of Elderly Patients With Supraventricular Tachyarrhythmias and Ventricular Tachycardia

Radiofrequency catheter ablation was performed in 100 men and 81 women, mean age 78 +/- 5 years, referred for ablation of atrial flutter, supraventricular tachycardia, and ventricular tachycardia, and for ablation of the atrioventricular junction with permanent pacemaker implantation in patients with atrial fibrillation and a rapid ventricular rate not controlled by drug therapy. A hematoma in 1 of 182 ablation procedures (<1%) was the only complication. Radiofrequency catheter ablation was successful in treating 63 of 70 patients (90%) with atrial flutter, in treating 60 of 66 patients (91%) with supraventricular tachycardia, in treating 2 of 2 patients (100%) with ventricular tachycardia, and in ablating the atrioventricular junction in 43 of 44 patients (98%) with atrial fibrillation and a rapid ventricular rate not controlled by drug therapy.

Cryoablation versus radiofrequency ablation for treatment of pediatric atrioventricular nodal reentrant tachycardia: Initial experience with 4-mm cryocatheter

Initial reports have shown cryoablation to be safe and efficacious for treatment of atrioventricular nodal reentrant tachycardia (AVNRT). No direct comparisons of cryoablation vs radiofrequency (RF) catheter ablation in pediatric patients have been made. The purpose of this study was to compare the outcomes of cryothermal vs RF catheter ablation for treatment of AVNRT in pediatric patients. We retrospectively reviewed consecutive ablation procedures for treatment of AVNRT at a single arrhythmia center. The RF group consisted of patients who underwent RF ablation from 2002 until cryothermy became available. The cryoablation group consisted of patients who underwent cryothermal ablation from 2004 to 2005. The groups were compared for procedural and electrophysiologic outcomes. RF (n = 60, age 14 +/- 4 years) and cryoablation (n = 57, age 14 +/- 4 years) groups had similar demographic and baseline parameters. Procedural times were shorter in the RF group (RF ablation 112 +/- 31 minutes vs cryoablation 148 +/- 46 minutes, P < .001). Fluoroscopy times were comparable (RF ablation 21 +/- 15 minutes vs cryoablation 20 +/- 13 minutes, P = .77). In an intention-to-treat analysis, success of the procedure was 100% for RF ablation and 95% for cryoablation (P = .11). No permanent AV block occurred in either group. Recurrence rates were higher for the cryoablation group, but this did not reach statistical significance (RF ablation 2% vs cryoablation 8%, P = .19). Cryoablation appears to be similar to RF for ablation of AVNRT with respect to short-term efficacy and safety of the procedure in a pediatric population. Recurrence rates are higher with cryoablation.

Long-term clinical outcome of right bundle branch radiofrequency catheter ablation for treatment of bundle branch reentrant ventricular tachycardia.

The study assessed the long-term outcome of patients undergoing radiofrequency ablation of the right bundle for bundle branch reentrant ventricular tachycardia. Bundle branch reentrant tachycardia was diagnosed in 16 patients (ejection fraction 31% +/- 15%) who underwent electrophysiology study in our laboratory. All patients had His-Purkinje system conduction delay with mean HV interval of 68 +/- 8 ms. After ablation, right bundle branch block developed in 15 patients. One patient developed complete heart block, which was anticipated. One patient died of heart failure 9 months after ablation. Two patients were successfully bridged to heart transplantation 0.5 and 13 months, respectively, after ablation. Two patients received implantable defibrillators for other ventricular tachycardias. One patient had syncope 11 months after ablation, but there was no evidence of ventricular tachycardia or heart block in repeat electrophysiology study. This patient died suddenly 29 months after ablation. The remaining nine patients were alive and well for a mean follow-up of 19 +/- 10 months. Radiofrequency ablation of the right bundle branch is an effective therapy for treatment of bundle branch reentrant ventricular tachycardia. Survival is excellent provided that other types of ventricular tachycardia, when present, are treated as well. This technique may be helpful in management of patients who have unacceptable frequent shocks from their implanted defibrillators and may be helpful in avoiding implantation of such a device completely in others. In some patients with terminal heart failure and incessant ventricular tachycardia, this procedure can function as a bridge to cardiac transplantation.

Idiopathic Left Ventricular Tachycardia: New Insights, into Electrophysiological Characteristics and Radiofrequency Catheter Ablation

This study was performed to investigate the electrophysiological characteristics of idiopathic left ventricular tachycardia and to determine the feasibility of radiofrequency catheter ablation for nonpharmacological cure. The underlying electrophysiological mechanism of idiopathic left ventricular tachycardia with right bundle branch block morphology and left-axis deviation is presently not known. Additionally, only limited data describing the results of radiofrequency catheter ablation for treatment of idiopathic left ventricular tachycardia so far exist. Electrophysiological studies and radiofrequency catheter ablation were performed in 5 patients (3 male and 2 female, mean age 31 +/- 10 years) with idiopathic left ventricular tachycardia (cycle length 376 +/- 72 msec). The patients had a history of recurrent palpitations of 4 +/- 1 years and had been treated unsuccessfully with 2 +/- 1 antiarrhythmic drugs. Sustained ventricular tachycardia with right bundle branch block morphology and left- or right-axis deviation was documented in all patients. Inducibility with critically timed ventricular extrastimuli, inverse relationships of the coupling interval of the initiating extrastimulus and the interval to the first beat of the tachycardia, continuous diastolic or mid-diastolic electrical activity during ventricular tachycardia, and fragmented late potentials during sinus rhythm suggested reentrant activation as the underlying mechanism in three patients. On the other hand, induction dependent on isoproterenol infusion and rapid ventricular pacing and exercise inducibility indicated different electrophysiological characteristics in the remaining two patients. During electrophysiological study, intravenous verapamil terminated ventricular tachycardia in all patients, whereas ventricular tachycardia did not respond to intravenous adenosine, autonomic maneuvers, or intravenous beta-blocking agent esmolol. Catheter mapping revealed earliest endocardial activation during ventricular tachycardia in different areas of the left ventricular septum being distributed from the base to the mid-apical portion of the septum in all patients. In 4 of 5 patients, radiofrequency catheter ablation (median number of pulses 4, range 1-9) resulted in complete abolition of idiopathic left ventricular tachycardia during a follow-up of 4-43 months (median 10) without antiarrhythmic drugs. Successful target sites for catheter ablation included continuous diastolic or mid-diastolic electrical activity during ventricular tachycardia and late potentials during sinus rhythm (2 patients), polyphasic fragmented presystolic potentials during ventricular tachycardia (1 patient), and pace mapping with identical QRS morphology compared to the ventricular tachycardia and "earliest" detectable activity during tachycardia (1 patient). No procedure related complications occurred. Two different patterns of electrophysiological properties of idiopathic left ventricular tachycardia were observed, indicating that this arrhythmia entity does not represent a homogeneous group. The "origin" of the tachycardias as identified by successful radiofrequency catheter ablation was located in different areas of the left ventricular septum and was distributed from the base to the mid-apical region. Radiofrequency catheter ablation was an effective and safe treatment modality in most of these patients. Distinct target site characteristics for successful catheter ablation including polyphasic diastolic activity during tachycardia and fragmented late potentials during sinus rhythm could be identified.

Effectiveness of radiofrequency catheter ablation for treatment of atrial tachycardia

Catheter ablation has been used to treat atrioventricular node reentrant and atrioventricular reentrant tachycardias with extremely high success rates. The suitability of catheter ablation for treatment of atrial tachycardia, a much less common type of supraventricular tachycardia, has not been well addressed. Fifteen patients (8 females) ranging from 10 to 83 years (mean 38 ± 22) were referred for catheter ablation of supraventricular tachycardia. The diagnosis of atrial tachycardia was established by standard electrophysiologic techniques. A combination of activation and pace mapping was used to identify a suitable site for radiofrequency current catheter ablation. Medical therapy was unsuccessful in all but 1 patient. Two patients had surgically corrected congenital heart disease, 2 had coronary artery disease and 1 had dilated cardiomyopathy. Seven patients had depressed left ventricular function. Six patients had incessant tachycardias. Presumed tachycardia mechanism was automatic in 11 patients and reentrant in 4. Mean tachycardia cycle length was 372 ± 74 ms. Catheter ablation was acutely successful in 12 patients (80%) with application of 11.1 ± 6.6 lesions at a mean voltage of 60 ± 9 V. In the other 3 patients, 16 to 38 lesions were applied. At a mean follow-up of 18.5 ± 6.5 months, 2 patients have had recurrences with different P-wave morphologies and underwent a second successful catheter ablation procedure. An additional 2 patients had recurrences with the same P-wave morphology and 1 underwent a second successful catheter ablation procedure. Thus, radiofrequency ablation can be used in a diverse population of patients with atrial tachycardia with an acute success rate of 80% and a long-term success rate of 73%.

Radiofrequency catheter ablation for treatment of Wolff-Parkinson-White syndrome — short- and long-term follow-up

One hundred and twenty-five patients with accessory pathways mediated tachyarrhythmias underwent radiofrequency ablation. Right-sided accessory pathways were ablated from the atrial aspect of the tricuspid anulus (all from the femoral vein approach) and the left-sided accessory pathways were ablated from the atrial or ventricular aspect of the mitral anulus. Immediately after the procedures, 3 of 8 accessory pathways (38%) and 131 of 137 accessory pathways (95%) were ablated successfully with radiofrequency through a small-tip (2 mm) and a large-tip (4 mm) electrode catheter, respectively. Seven of the 11 accessory pathways that failed radiofrequency ablation had a later successful direct current ablation. During follow-up (3 to 22 months), serial electrophysiological study showed that 11 of the 114 patients (10%) with successful ablation had return of accessory pathway conduction (2 had recurrence of tachycardia, 2%). Complications included accidental AV block (1 patient), cardiac tamponade (1 patient) and possible aortic dissection (1 patient). Transient proarrhythmic effects (more atrial and ventricular premature beats) were seen during the first week and sustained ventricular tachyarrhythmias were not inducible. In a successful session, procedure and radiation exposure times (including the time for diagnostic procedures) were 3.8 ± 0.2 h and 45 ± 4 min, respectively. This study confirms that radiofrequency ablation with a large-tip electrode catheter is an effective and relatively safe nonsurgical method for treatment of Wolff-Parkinson-White syndrome, with a low complication and recurrence rate.

Radiofrequency catheter ablation for treatment of bundle branch reentrant ventricular tachycardia: Results and long-term follow-up

Seven of 120 consecutive patients with inducible sustained ventricular tachycardia (from September 1, 1988 to January 1, 1991) had bundle branch reentrant tachycardia and underwent percutaneous radiofrequency ablation of the right bundle branch. The seven patients had been unsuccessfully treated with a mean of 3 ± 1 drugs. Four patients presented with syncope and three with aborted sudden death. The baseline electrocardiogram revealed a left bundle branch block pattern in three patients and an intraventricular conduction defect in four.The baseline HV interval was prolonged in each case (79 ± 2 ms). With use of programmed ventricular extrastimuli, sustained bundle branch reentrant tachycardia was inducible in all patients at a mean cycle length of 283 ± 17 ms (range 230 to 350). Bundle branch reentrant tachycardia characteristics included atrioventricular dissociation, a His deflection that preceded each QRS complex and spontaneous His to His variation that preceded changes in ventricular tachycardia cycle length.A quadripolar catheter was positioned across the tricuspid valve with the distal electrode tip of the catheter near the right bundle branch. One to three applications of continuous unmodulated radiofrequency current at 300 kHz between the distal electrode and a large posterior skin patch resulted in complete right bundle branch block in all patients, after which none had inducible bundle branch reentrant tachycardia on restudy. On restudy, three of the seven patients had ventricular tachycardia of myocardial origin (not bundle branch reentry). One patient required no therapy; drug or defibrillator therapy was used in the others. After a mean follow-up interval of 12 ± 3 months (range 6 to 29) complete right bundle branch block persisted, there were no spontaneous episodes of ventricular tachycardia and no patient required a permanent pacemaker.Radiofrequency catheter ablation of the right bundle branch is easily performed and is a safe and effective treatment for bundle branch reentrant tachycardia. It is probably the procedure of choice for these highly symptomatic patients.