Tachycardia In Congenital Heart Disease Research Articles

Incidence of Atrial Fibrillation After Radiofrequency Catheter Ablation for Atrial Tachycardia in Congenital Heart Disease

BackgroundAtrial tachycardia (AT) and atrial fibrillation (AF) coexist in 30% of congenital heart disease (CHD) patients. Successful atrial tachycardia catheter ablation (ATCA) might prevent AF. Data on new-onset AF after ATCA in CHD is scarce. ObjectivesThis study aimed to evaluate the incidence of new-onset AF after ATCA and to assess clinical characteristics associated with new-onset AF after ATCA in CHD. MethodsCHD patients referred for ATCA to 3 European centers were included. New occurrence of AF was defined as electrocardiographic documentation of AF after any ATCA procedure in patients without history of AF. ResultsIn 277 CHD patients (median age 37 years [Q1, Q3: 23, 49 years], 58% men, 59 [21%] simple, 111 [40%] moderate, and 107 [39%] complex CHD), AF occurred in 25 patients (9%) a median of 8 months (Q1, Q3: 4, 27 months) after ATCA. New-onset AF was persistent in the majority of the patients (17 of 25 [63%]). Patients with new-onset AF were older (44 years [Q1, Q3: 29, 55 years] vs 36 years [Q1, Q3: 23, 49 years]; P = 0.009) and more frequently had simple CHD (13 of 25 [52%] vs 46 of 252 [18%], respectively; P < 0.0001). Acute ATCA success rates were similar in patients with and without AF (52% vs 48%; P = 0.429). Simple CHD was an independent predictor of new-onset AF during follow-up. ConclusionsIn our large cohort of patients with congenital heart disease, new-onset AF after ablation for AT occurred in only 9% of the patients. AF occurred without AT recurrence and was persistent in the majority of patients.

Catheter Ablation of Atrioventricular Nodal Reentrant Tachycardia in Patients With Congenital Heart Disease.

Atrioventricular (AV) nodal reentrant tachycardia represents the most common regular supraventricular arrhythmia in humans, and catheter ablation of the so called slow AV nodal pathway has been effectively performed for decades. In patients with congenital heart disease, a combination of different factors makes catheter ablation of AV nodal reentrant tachycardia substrate particularly challenging, including abnormal venous access to intracardiac structures, abnormal intracardiac anatomy, potentially deviant and often unpredictable sites of the specific conduction system, loss of traditional anatomic landmarks, and congenital cardiac surgery that may complicate the access to the AV nodal area. Published experiences have confirmed the efficacy and the relative safety of such procedures when performed by experts, but the risk of complications, in particular AV block, remains non-negligible. A thorough knowledge and understanding of anatomic and electrical specificities according to underlying phenotype are essential in addressing these complex cases. Considering the major consequences associated with AV block in patients with complex congenital heart disease, particularly those without low risk access for transvenous ventricular pacing (eg, single ventricle physiology or Eisenmenger syndrome), the individual risk-benefit ratio should be carefully evaluated. The decision to defer ablation may be the wisest approach in selected patients with either infrequent or hemodynamically tolerated arrhythmias, or when the location of the AV conduction pathways remains uncertain. This narrative review aims to synthetize existing literature on catheter ablation of AV nodal reentrant tachycardia in congenital heart disease, to present main features of common associated pathologies, and to discuss approaches to mapping and safely ablating the slow AV nodal pathway in challenging cases.

Intra-atrial re-entrant tachycardia in congenital heart disease: types and relation of isthmus to atrial voltage.

Intra-atrial re-entrant tachycardia (IART) is a frequent and severe complication in patients with congenital heart disease (CHD). Cavotricuspid isthmus (CTI)-related IART is the most frequent mechanism. However, due to fibrosis and surgical scars, non-CTI-related IART is also frequent. The main objective of this study was to describe the types of IART and circuit locations and to define a cut-off value for unhealthy tissue in the atria. This observational study included all consecutive patients with CHD who underwent a first ablation procedure for IART from January 2009 to December 2015 (94 patients, 39.4% female, age: 36.55 ± 14.9 years, 40.4% with highly complex cardiac disease). During the study, 114 IARTs were ablated (1.21 ± 0.41 IARTs per patient). Cavotricuspid isthmus-related IART was the only arrhythmia in 51% (n = 48) of patients, non-CTI-related IART was the only mechanism in 27.7% (n = 26), and 21.3% of patients (n = 20) presented both types of IART. In cases of non-CTI-related IART, the most frequent location of IART isthmus was the lateral or posterolateral wall of the venous atria, and a voltage cut-off value for unhealthy tissue in the atria of 0.5 mV identified 95.4% of IART isthmus locations. In our population with a high proportion of complex CHD, CTI-related IART was the most frequent mechanism, although non-CTI-related IART was present in 49% of patients (alone or with concomitant CTI-related IART). A cut-off voltage of 0.5 mV could identify 95.4% of the substrates in non-CTI-related IART.

Mapping and ablation of supraventricular tachycardia in pediatric and congenital heart disease patients

The past two decades have witnessed astounding advances in the efficacy and safety of catheter ablation techniques as definitive therapy of supraventricular tachycardia, with application to an ever widening spectrum of pediatric and congenital heart disease patients. This review covers both general considerations in pediatric ablation and technical pearls specific to a variety of ablation targets. Tools of ablation, indications for ablation, historical outcomes and unique considerations in children and complex congenital heart disease are addressed. This is followed by discussion of ablation of accessory pathways, AV node reentrant tachycardia, focal atrial tachycardia in structurally normal hearts and atrial tachycardia in congenital heart disease.