Epicardial ablation of tachyarrhythmia in children: Experience at two academic centers

CT-scan-guided-irrigated trans-catheter ablation of epicardial accessory pathways in the coronary sinus: safety and feasibility in pediatric patients

BACKGROUND

The most common site of epicardial APs is posterior-septal, and ablation from the coronary sinus (CS) or its main tributaries is needed. However, particularly in children, it can carry a considerable risk of complications, such as coronary artery (CA) injury, CS damage, and perforation. This study aims to assess the efficacy and safety of computed tomography (CT)-scan-guided-irrigated trans-catheter (TC) ablation of epicardial APs through the CS in children.

METHODS

Twenty-four children (19 males; mean age 13.8 ± 2.6) with posterior-septal and left posterior epicardial APs who underwent an endocavitary electrophysiological study (EPS) and TC ablation from the CS were enrolled in this study. All patients underwent a CT scan to visualize the CS and its branches and their proximity to the CAs before the ablation. Clinical, electrophysiological and follow-up data were collected.

RESULTS

Acute success rate was 87.5% (21 out of 24 procedures). No complications occurred. In 16 (66.7%) patients, the ablation site was detected at the proximal CS, in two (8.3%) patients in the mid-proximal CS and in six (25%) in the middle cardiac vein (MCV). Ablation was achieved using an irrigated radiofrequency (RF) catheter in all patients and without the use of fluoroscopy in 20 patients (83.3%). Over a median follow-up of 15.1 months (IQR 2.5-32.3), no recurrences or complications occurred.

CONCLUSION

Epicardial posterior-septal and left posterior APs, in the area of CS or MCV, can be definitively eliminated in most children using CT-scan-guided electro-anatomical mapping and transvenous irrigated RF ablation.

When to ablate in Brugada and early repolarization syndromes

INTRODUCTION

Mapping advances have expanded both the feasibility and benefits of ablation as a therapeutic approach, including in the treatment of two heart conditions that contribute to sudden cardiac death in young people: Brugada syndrome (BrS) and early repolarization syndrome (ERS). Although these conditions share a number of similarities, debates persist regarding the underlying pathophysiology and origin of the ventricular arrhythmias associated with them.

AREAS COVERED

By synthesizing available data (PubMed), including current recommendations, pathophysiological insights and case reports, patient registries, our aim is to elucidate and establish the nuanced role of radiofrequency ablation (RFA) in therapeutic management.

EXPERT OPINION

RFA is a particularly promising approach in BrS, with a proven long-term benefit. Concerning ERS, RFA seems to be interesting at the price of more complex procedures with more nuanced results.

Percutaneous epicardial pacing in infants using direct visualization: A feasibility animal study

BACKGROUND

Pacemaker implantation in infants and small children is limited to epicardial lead placement via open chest surgery. We propose a minimally invasive solution using a novel percutaneous access kit.

OBJECTIVE

To evaluate the acute safety and feasibility of a novel percutaneous pericardial access tool kit to implant pacemaker leads on the epicardium under direct visualization.

METHODS

A custom sheath with optical fiber lining the inside wall was built to provide intrathoracic illumination. A Veress needle inside the illumination sheath was inserted through a skin nick just to the left of the xiphoid process and angled toward the thorax. A needle containing a fiberscope within the lumen was inserted through the sheath and used to access the pericardium under direct visualization. A custom dilator and peel-away sheath with pre-tunneled fiberscope was passed over a guidewire into the pericardial space via modified Seldinger technique. A side-biting multipolar pacemaker lead was inserted through the sheath and affixed against the epicardium.

RESULTS

Six piglets (weight 3.7-4.0 kg) had successful lead implantation. The pericardial space could be visualized and entered in all animals. Median time from skin nick to sheath access of the pericardium was 9.5 (interquartile range [IQR] 8-11) min. Median total procedure time was 16 (IQR 14-19) min. Median R wave sensing was 5.4 (IQR 4.0-7.3) mV. Median capture threshold was 2.1 (IQR 1.7-2.4) V at 0.4 ms and 1.3 (IQR 1.2-2.0) V at 1.0 ms. There were no complications.

CONCLUSION

Percutaneous epicardial lead implantation under direct visualization was successful in six piglets of neonatal size and weight with clinically acceptable acute pacing parameters.

3D transvenous radiofrequency ablation of manifest epicardial posterior-septal accessory pathways in children: Can technology innovations improve the outcome?

INTRODUCTION

The aim of the study was to revise our more recent experience about epicardial posterior-septal accessory pathways radiofrequency transcatheter ablation in children and young patients using a transvenous approach through the coronary sinus, to understand if new mapping and ablation technologies can increase success rate and safety.

METHODS AND RESULTS

Twenty children (mean age 13 ± 3 years) with epicardial posterior-septal accessory pathways (14 in coronary sinus and 6 in the middle cardiac vein) underwent radiofrequency transcatheter ablation with CARTO-3® system with help of the CARTO-Univu® module. Acute success rate was 73%. No patient was lost to follow-up (mean time 11.4 ± 9 months). The recurrence rate was 19%. Two patients underwent a successful redo-procedure; the overall long-term success rate was 65%. Navistar® catheter presented the highest acute success rate in the coronary sinus. Navistar SmartTouch® was the only catheter that did not present recurrences after the acute success, and it was successfully used in two patients previously unsuccessfully treated with a Navistar ThermoCool®. Acute success rate was 79% without image integration with angio-CT, while it was 63% after the introduction of CARTO-Merge®.

CONCLUSION

Epicardial posterior-septal accessory pathways can be definitively eliminated by transvenous radiofrequency transcatheter ablation in more than half of the cases in children. Acute success rate does not seem to depend on catheters used, but contact-force catheter seems to be useful in cases with recurrences. Image integration with cardiac-CT does not increase success rate, but it is useful to detect coronary sinus alterations to better guide ablation strategy.

Successful Ablation of an Epicardial Accessory Pathway via the Subxiphoid Approach in a Child

Data is scarce regarding epicardial ablation in children. I herewith present a case of successful epicardial ablation in a child with previous unsuccessful attempts at endocardial ablation. This report could be used to guide further such attempts.

Epicardial Ablation Complications

The percutaneous epicardial approach has become an adjunctive tool for electrophysiologists to treat disparate cardiac arrhythmias, including accessory pathways, atrial tachycardia, and particularly ventricular tachycardia. This novel technique prompted a strong impulse to perform epicardial access as an alternative strategy for pacing and defibrillation, left atrial appendage exclusion, heart failure with preserved ejection fraction, and genetically engineered tissue delivery. However, because of the incremental risk of major complications compared with stand-alone endocardial ablation, it is still practiced in a limited number of highly experienced centers across the world.

A novel percutaneous stabilizing sheath for minimal invasive epicardial echocardiography and ablation

PURPOSE

Epicardial ablation and mapping are critical adjuncts to the electrophysiologist's approach to arrhythmias; however, ablation within the epicardial space requires the avoidance of coronary arteries (CA). We aimed to evaluate the feasibility and performance of a novel-stabilizing ablation sheath housing an intracardiac echocardiography (ICE) catheter to (1) obtain Epicardial Echocardiography (EE) images, (2) visualize CAs, and (3) enable targeted delivery of radiofrequency energy away from visualized CAs.

METHODS

We designed a sheath that could enclose a regular ICE catheter. This sheath has flanges and a balloon, with three interspersed windows surrounded by an electrode. In an acute canine model (N = 6), the sheath was manipulated within the pericardial space to visualize cardiac structures and CAs. Visualization of CAs was confirmed with angiography. Ablation was then performed through the window either proximal or distal to the CA.

RESULTS

The novel sheath was successfully deployed in six canines, with no acute procedural complications. Images with an excellent spatial resolution of cardiac structures were obtained including the right ventricular outflow tract; aortic, pulmonary, and mitral valves; and left atrial appendage. CAs were successfully visualized, and ablation from a sheath window either proximal or distal to the CA did not produce angiographic or histopathological evidence of CA damage despite evidence of acute injury to the adjacent ablated myocardium.

CONCLUSIONS

This novel percutaneous stabilizing sheath was able to successfully obtain high-quality EE images as well as provide a non-fluoroscopic intra-procedural means to visualize CAs. Use of this sheath enabled successful delivery of energy to avoided CA damage.