Radiofrequency ablation of a concealed right anterior accessory pathway associated with right atrial diverticulum in a child

A 9-year-old boy had refractory supraventricular tachycardia and a right atrial (RA) diverticulum as diagnosed by ultrafast computed tomography. An electrophysiological study under transesophageal echocardiography guidance revealed a concealed right anterior accessory pathway passing through the body of the RA diverticulum. Radiofrequency ablation was performed to eliminate retrograde ventriculoatrial conduction.     

Electrophysiologic characteristics and radiofrequency catheter ablation in children with Wolff-Parkinson-White syndrome

BACKGROUND: The majority of cardiac arrhythmias in children are supraventricular tachycardia, which is mainly related to an accessory pathway (AP)-mediated reentry mechanism. The investigation for Wolff-Parkinson-White (WPW) syndrome in adults is numerous, but there is only limited information for children. This study was designed to evaluate the specific electrophysiologic characteristics and the outcome of radiofrequency (RF) catheter ablation in children with WPW syndrome. METHODS: From December 1989 to August 2005, a total of 142 children and 1,219 adults with atrioventricular reentrant tachycardia (AVRT) who underwent ablation at our institution were included. We compared the clinical and electrophysiologic characteristics between children and adults with WPW syndrome. RESULTS: The incidence of intermittent WPW syndrome was higher in children (7% vs 3%, P=0.025). There was a higher occurrence of rapid atrial pacing needed to induce tachycardia in children (67% vs 53%, P=0.02). However, atrial fibrillation (AF) occurred more commonly in adult patients (28% vs 16%, P=0.003). The pediatric patients had a higher incidence of multiple pathways (5% vs 1%, P<0.001).Both the onset and duration of symptoms were significantly shorter in the pediatric patients. The antegrade 1:1 AP conduction pacing cycle length (CL) and antegrade AP effective refractory period (ERP) in children were much shorter than those in adults with manifest WPW syndrome. Furthermore, the retrograde 1:1 AP conduction pacing CL and retrograde AP ERP in children were also shorter than those in adults. The antegrade 1:1 atrioventricular (AV) node conduction pacing CL, AV nodal ERP, and the CL of the tachycardia were all shorter in the pediatric patients. CONCLUSION: This study demonstrated the difference in the electrophysiologic characteristics of APs and the AV node between pediatric and adult patients. RF catheter ablation was a safe and effective method to manage children with WPW syndrome.     

Radiofrequency catheter ablation of an accessory pathway in a patient with Wolff-Parkinson-White and Kartagener's syndrome

We report a case of a manifest left free wall accessory pathway in a patient with Kartagener's syndrome and recurrent episodes of orthodromic atrioventricular reentrant tachycardia. To the best of our knowledge, it is the first report of Wolff-Parkinson-White syndrome associated with Kartagener's syndrome. Situs inversus and mirror image dextrocardia occurred with no additional detectable cardiac structural abnormalities. Diagnostic and therapeutic electrophysiological study was carried out via transaortic approach and a left-to-right reversal of monoplane fluoroscopic image.     

Radiofrequency catheter ablation of "typical" atrial flutter in a patient with Kartagener's syndrome

Kartagener's syndrome and radiofrequency catheter ablation for the treatment of atrial flutter have been well described in separate reports. This case report includes both in describing a patient with Kartagener's syndrome who had medically refractory atrial flutter that was successfully treated with radiofrequency catheter ablation.     

Right Atrial Diverticulum Presenting as Wolff-Parkinson-White Syndrome

A 7-year-old male presenting with Wolff-Parkinson-White syndrome and tachycardia was suspected by echocardiographic and magnetic resonance imaging evaluation to have an associated pericardial cyst anterior to the right atrium and ventricle. Electrophysiological evaluation demonstrated short antegrade and retrograde accessory connection refractory periods, with inducible orthodromic atrioventricular reentrant tachycardia. Surgical observation revealed a rare congenital right atrial diverticulum bridging the anterior right atrioventricular groove, with the functional accessory connection lateralized to the medial aspect of this structure. Endocardial and epicardial incisions and cryolesions placed along the anterior right atrioventricular groove initially appeared successful, but preexcitation recurred within 4 weeks postoperatively.     

Ablation of a Left-Sided Free-Wall Accessory Pathway by Percutaneous Catheter Application of Radiofrequency Current in a Patient with the Wolff-Parkinson-White Syndrome

A case is presented of a 20-year-old woman with a history of three episodes of syncope within the last 4 years, which was caused by a rapid ventricular response to atrial fibrillation via a left-sided posterior accessory pathway. A variety of antiarrhythmic agents had failed to control the arrhythmia. Using a novel dual catheter approach, with one catheter in the coronary sinus and an adjacent catheter in the left ventricle close to the mitral annulus, accessory pathway conduction was successfully interrupted by two radio-frequency current applications between the tip electrodes of the two catheters. During follow-up, 12-lead electrocardiograms have been normal and the patient has been asymptomatic.     

Radiofrequency Catheter Ablation for Wolff-Parkinson-White Syndrome Associated with a Coronary Sinus Diverticulum

The case of a patient with Wolff-Parkinson-White syndrome undergoing attempted radiofrequency catheter ablation of a left posterior paraseptal accessory pathway is described. Coronary sinus venography revealed the presence of a large diverticulum attaching near the os. The electrogram recorded from a catheter placed in the narrow neck of the diverticulum revealed a very short atrioventricular time during sinus rhythm. The pathway was easily ablated using radiofrequency energy applied in the neck of the diverticulum, after multiple failed attempts at catheter ablation from the endocardial surface of the mitral annulus. Our report emphasizes the importance of searching for a coronary sinus diverticulum in all patients with posterior accessory pathways undergoing catheter ablation.     

Catheter ablation of atrial fibrillation: long-term outcomes

The benefits of percutaneous coronary intervention (PCI) can be offset by periprocedural complications such as acute vessel closure and stent thrombosis in the absence of adequate antiplatelet and antithrombotic therapy. Additionally, conditions occurring after 30 days post-PCI, such as in-stent restenosis or late stent thrombosis can occur. Excess antithrombotic therapy, on the other hand, carries a risk of major gastrointestinal or intracranial bleeding as well as vascular access site bleeding complications. In this review, evidence related to the various pharmacological agents for reduction of stent thrombosis available to clinicians during and after PCI will be explored.     

Catheter ablation as first-line therapy for patients with symptomatic atrial fibrillation

Atrial fibrillation (AF) is a common clinical problem that is associated with an impaired quality of life, thromboembolism, heart failure and death. Medical treatment of AF remains suboptimal and is associated with potentially serious side effects. The disappointing outcomes with medical therapy have spurred the age of catheter ablation of AF. In the last 10 years, catheter ablation of AF has evolved dramatically and has been shown to be superior to medical therapy in multiple studies. As a result, catheter ablation may be offered to the symptomatic patient as first-line therapy in lieu of antiarrhythmic medications, which have limited efficacy and are associated with significant toxicity.     

Noncavotricuspid isthmus-dependent right atrial tachycardia after paroxysmal atrial fibrillation ablation

Background: Atrial tachycardia (AT) is commonly encountered after atrial fibrillation (AF) ablation. But no study exclusively on noncavotricuspid isthmus‐dependent right AT (NCTI‐RAT) post‐AF ablation has been reported. The present study aims to describe its prevalence, electrophysiological mechanisms, and ablation strategy and to further discuss its relationship with AF. Methods: From July 2006 to November 2009, 350 consecutive patients underwent catheter ablation for paroxysmal AF. A total of seven patients (2.0%) developed NCTI‐RAT after left atrium ablation for AF. In these highly selected patients (two male, mean age 54 ± 11 years, mean left atrium diameter of 34 ± 7 cm), all had circumferential pulmonary vein isolation in their initial procedures and three of them had additional complex fractionated electrograms ablation in the left atrium and the coronary sinus. Results: Totally, nine NCTI‐RATs were mapped and successfully ablated in the right atrium with a mean cycle length of 273 ± 64 ms in seven patients. Five ATs in three patients were electrophysiologically proved to be macroreentry and the remaining four were focal activation. All the ATs were successfully abolished by catheter ablation. After a mean follow‐up of 29 ± 15 months post‐AT ablation, all patients were free of AT and AF off antiarrhythmic drugs. Conclusions: NCTI‐RAT is relatively less common post‐AF ablation. Totally, 2.0% of paroxysmal AF patients were revealed to have NCTI‐RAT. (PACE 2011; 34:391–397)     

Wolff-Parkinson-White syndrome concomitant with asymptomatic Brugada syndrome

A 29-year-old man was referred for electrophysiological testing and radiofrequency ablation because of repeated episodes of palpitation over 2 years. A 12-lead electrocardiogram during sinus rhythm showed manifest Wolff-Parkinson-White syndrome and during palpitation showed narrow QRS tachycardia at a rate of 213 beats/min. Following successful radiofrequency ablation of the left anterolateral accessory pathway, sustained atrial fibrillation was induced by atrial extrastimulation. Cibenzoline (2 mg/kg body weight) was injected to terminate atrial fibrillation. ST-T segment elevation in the right precordial leads was observed following cibenzoline administration. Ventricular fibrillation was reproducibly induced by ventricular extrastimuli (S1: 600 ms, S2: 220 ms, S3: 210 ms).     

Dependency on Atrial Electrophysiological Properties of Appearance of Paroxysmal Atrial Fibrillation in Patients with Wolff-Parkinson-White Syndrome: Evidence from Atrial Vulnerability Before and After Radiofrequency Catheter Ablation and Surgical Cryoablation

The pathogenesis of paroxysmal atrial fibrillation in patients with Wolff-Parkinson-White syndrome and the effects of elimination of accessory pathways on the appearance of atrial fibrillation are still controversial. Fifty-four patients with Wolff-Parkinson-White syndrome were classified into three groups: a No AFgroup (n = 24), patients without paroxysmal atrial fibrillation; an RF-AF Group (n =12), patients with paroxysmal atrial fibrillation whose accessory pathways were eliminated using radiofrequency catheter ablation; and a Cryo-AF Group (n = 18), patients with paroxysmal atrial fibrillation whose accessory pathways were eliminated with surgical Cryoablation. The electrophysiological characteristics of each group were evaluated prior to and following the elimination of their accessory pathways. As indices of atrial vulnerability, the presence of fragmented atrial activity and repetitive atrial firing zones were assessed. Deducibility of atrial fibrillation was significantly reduced following ablation of accessory pathways in the Cryo-AF group (83.3%-5.6%, P < 0.0001), while it was unchanged in the RF-AF group (83.3%-75%). In preablation studies, the effective refractory periods of the atrium in the RF-AF group and the Cryo-AF group were significantly shorter compared with the No AF group (204 ± 18 ms, 197 ± 16 ms vs 246 ± 44 ms, respectively, P < 0.0001). Following ablation, the effective refractory period for patients in the Cryo-AF group was significantly prolonged compared with before ablation (197 ± 16 ms to 232 ± 24 ms, P < 0.0001). As a result of this prolongation of the effective refractory period of the atrium, the fragmented atrial activity and repetitive atrial response zones narrowed following ablation in the Cryo-AF group, but not in the RF-AF group. Therefore, the pathogenesis of atrial fibrillation in patients with Wolff-Parkinson-White syndrome may depend on the refractory period of the atrium rather than on the presence of accessory pathways.     

The different electrophysiological characteristics in children with Wolff-Parkinson-White syndrome between those with and without atrial fibrillation

Atrioventricular reciprocating tachycardia (AVRT) is known to be the most common supraventricular tachycardias in childhood. Because AF with rapid ventricular response may degenerate to ventricular fibrillation through conduction of accessory pathways (APs), it can be potentially life-threatening in some pediatric patients with WPW syndrome. However, information about WPW syndrome children associated with AF is limited. The purpose of this study was to investigate the specific electrophysiological characteristics in pediatric patients with WPW syndrome and AF. From July 1992 to February 2002, 51 pediatric patients with manifest WPW syndrome and documented AVRT underwent electrophysiological study and radiofrequency catheter ablation. In these patients, two (4%) were found to have several spontaneous episodes of AF recognized on 12-lead standard ECG or 24-hour Holter monitoring. Eleven (22%) patients had AF induced by rapid atrial pacing during the baseline procedure of electrophysiological study. The children with manifest WPW syndrome were divided into two groups: those with AF (group 1; n = 11) consisted of seven male and four female children (mean age 15 +/- 3 years, range 10-18), and those without AF (group 2; n = 40) consisted of 22 boys and 18 girls (mean age 16 +/- 3 years, range 7-18). The study excluded a patient who had Ebstein's anomaly associated with moderate tricuspid regurgitation and right atrial enlargement. The onset and duration of symptoms were not significantly different between the two groups. Comparing the electrophysiological characteristics, the atrial effective refractory period (ERP) was shorter in WPW syndrome children with AF (170 +/- 36 vs 190 +/- 38 ms, P = 0.041). This study demonstrated that the pediatric WPW syndrome patients with AF had different electrophysiological characteristics from those without AF.     

Catheter ablation for atrial fibrillation and intervention for pulmonary vein stenosis in a patient with Fontan circulation

Incidence of atrial fibrillation (AF) is high in patients with congenial heart disease. However, management of AF is challenging in these patients. Although radiofrequency catheter ablation (RFCA) is effective therapeutic option for AF, RFCA for AF is not common in patients who underwent Fontan operation. We present a 24‐year‐old woman with paroxysmal AF, who underwent lateral tunnel Fontan operation for functional single ventricle. Circumferential pulmonary vein isolation was successfully performed. However, significant pulmonary vein stenosis developed after RFCA. Pulmonary vein stenosis was successfully treated by transcatheter intervention.     

History of Wolff-Parkinson-White syndrome

While Drs. Wolff, Parkinson, and White fully described the syndrome that bears their names in 1930, prior case reports had already described the essentials. Over the ensuing century this syndrome has captivated the interest of anatomists, clinical cardiologists, and cardiac surgeons. Stanley Kent described lateral muscular connections over the atrioventricular (AV) groove, which he felt were the normal AV connections. The normal AV connections were, however, clearly described by His and Tawara. True right-sided AV connections were initially described by Wood et al., while Ohnell first described left free wall pathways. David Scherf is thought to be the first to describe our current understanding of the pathogenesis of the Wolff-Parkinson-White (WPW) syndrome in terms of a reentrant circuit involving both the AV node--His axis as well as the accessory pathway. This hypothesis was not universally accepted and many theories were applied to explain the clinical findings. The basics of our understandings were established by the brilliant work of Pick, Langendorf, and Katz who by using careful deductive analysis of ECGs were able to define the basic pathophysiological processes. Subsequently, Wellens and Durrer applied invasive electrical stimulation to the heart in order to confirm the pathophysiological processes. Sealy and his colleagues at Duke University Medical Center were the first to successfully surgically divide an accessory pathway and ushered in the modern area for curative therapy for these patients. Morady and Scheinman were the first to successfully ablate an accessory pathway (posteroseptal) using high-energy direct-current shocks. Subsequently, Jackman, Kuck, Morady, and a number of groups proved the remarkable safety and efficiency of catheter ablation for pathways in all locations using radiofrequency energy. More recently, Gallob et al. first described the gene responsible for a familial form of WPW. The current ability to cure patients with WPW is due to the splendid contributions of individuals from diverse disciplines from throughout the world.     

Catheter ablation vs. amiodarone plus losartan for prevention of atrial fibrillation recurrence in patients with paroxysmal atrial fibrillation

Background  Although amiodarone plus angiotensin II receptor blockers (ARBs) and catheter ablation may improve sinus rhythm maintenance of paroxysmal atrial fibrillation (AF), their clinical efficacies have not been compared. This prospective cohort study was designed to compare clinical efficacy of catheter ablation and amiodarone plus losartan on sinus rhythm maintenance in patients with paroxysmal AF.
Materials and methods  A total of 240 patients with paroxysmal AF were assigned to four groups. CPVA group ( n =  60) was treated with circumferential pulmonary vein ablation (CPVA), SPVI group ( n  = 60) with segmental pulmonary vein isolation, AMIO group ( n  = 60) with amiodarone and AMIO + LO group ( n  = 60) with amiodarone plus losartan. The endpoint was documented recurrence of AF > 30 s by Holter or conventional 12-lead ECG in the 1-year follow-up period.
Results  During 12 months of follow-up, the primary end point was reached in 28 patients in CPVA group, 14 patients in SPVI group, 25 patients in AMIO group and 13 patients in AMIO + LO group, respectively. The sinus rhythm in SPVI and AMIO + LO group were significant higher than that in CPVA and AMIO group ( P  < 0·01 and 0·025), and no difference between CPVA and AMIO group. The maintenance rate of sinus rhythm in SPVI group was similar to that in AMIO + LO group.
Conclusions  This study demonstrates that segmental pulmonary vein isolation in preventing AF recurrence is similar to amiodarone plus losartan, but it is superior to CPVA and amiodarone alone in patients with paroxysmal AF. Larger multicentre studies are needed to confirm its long-term outcomes.     

Direct Endocardial Recording and Catheter Ablation of an Accessory Pathway in a Patient with Incessant Supraventricular Tachycardia

A patient presented with incessant supraventricular tachycardia due to a concealed accessory pathway. The His bundle electrocardiogram showed a large discrete accessory pathway potential following ventricular activation and resulting in retrograde atrial activation. Percutaneous catheter ablation in the region of the accessory pathway potential left nodal conduction intact but prevented retrograde activation of the atria. Symptomatic tachycardia has not recurred. Direct endocardial recording of accessory pathway potentials is rare hut may offer the opportunity for catheter ablation.     

Catheter ablation for a right anteroseptal accessory pathway in a patient with an endocardial cushion defect

We report a radiofrequency catheter ablation for atrioventricular reentrant tachycardia in a patient with a right anteroseptal accessory pathway complicating an endocardial cushion defect. His bundle potential was recorded 20 mm posterior to the accessory pathway. In the presence of associated congenital heart disease, it is very important to understand the anatomy of the conduction system prior to radiofrequency catheter ablation.     

Catheter ablation of persistent and permanent atrial fibrillation: Bordeaux experience

The seminal observation that ectopics from the pulmonary veins may initiate paroxysmal atrial fibrillation (AF) heralded an era of potentially curative catheter ablation therapy for AF. In recent years, catheter ablation has been performed for not only paroxysmal but also persistent and permanent AF. It is anticipated that the number of procedures will continue to increase and the indication for catheter ablation will expand. This article details our experience with catheter ablation therapy for patients with persistent and chronic AF.