Remote-Controlled Magnetic Navigation and Ablation With 3D Image Integration as an Alternative Approach in Patients With Intra-Atrial Baffle Anatomy

Abstract

Background-Improvement in outcome of infants born with congenital heart defects has been accompanied by an increasing frequency of late arrhythmias. Ablation is difficult because of multiple tachycardias in the presence of complex anatomy with limited accessibility. We report on remote-controlled ablation using magnetic navigation in conjunction with 3D image integration in patients with previous intra-atrial baffle procedures. Methods and Results-Thirteen patients (8 male; age, 30.5Ϯ8 years) with supraventricular tachycardia (SVT) underwent catheter ablation. Group A had a medical history of a Mustard or Senning operation, whereas group B had undergone total cavopulmonary connection. A total of 26 tachycardias were treated in 17 procedures (median cycle length of 280 ms). Group A patients had more inducible SVTs than group B, and all index SVTs were located in the remainder of the morphological right atrium in all but 1 patient. Retrograde access through the aorta was performed and led to successful ablation, using magnetic navigation with a very low total radiation exposure (median of 3.8 minutes in group A versus 5.9 minutes in group B). Only 1 of 13 patients continued to have short-lasting SVTs despite 3 ablation procedures during a median follow-up time of Ͼ200 days. Conclusions-Remote-controlled catheter ablation by magnetic navigation in combination with accurate 3D image integration allowed safe and successful elimination of SVTs, using an exclusively retrograde approach, resulting in low radiation exposure for patients after intra-atrial baffle procedures (Mustard, Senning, or total cavopulmonary connection). (Circ Arrhythm Electrophysiol. 2012;5:131-139.)

Contemporary Outcomes of Supraventricular Tachycardia Ablation in Congenital Heart Disease

“…Some of these cases were reported previously. 10,12 Decision on selection of mapping system, catheter, and vascular access was made preoperatively by an experienced electrophysiologist on the basis of availability of equipment and each patient's condition. Procedures were classified into 3 groups according to the access and mapping technique: (1) 3D-EMS with conventional deflectable mapping/ablation catheter (group A), (2) 3D-EMS with RMN using normal femoral vein access (group B), and (3) 3D-EMS plus RMN in patients with difficult access (group C).…”

“…However, from our perspective RMN helped surmount 3 major hurdles seen in complex adult patients with CHD, namely, limited access to the target chamber, extensive atrial enlargement, and extensive wall thickness. 9,10,[17][18][19] Limited access is the consequence of complex intra/extracardiac anomaly and presence of intra-atrial baffles or artificial materials. We selected a retrograde aortic access and superior retrograde venous access for group C patients in our study.…”

“…[7][8][9] The main advantages of RMN, often used in conjunction with 3D-image integration, namely catheter maneuverability, stability, and precise delineation of the extracardiac and intracardiac anatomy can now be offered in particular situations, such as patients with limited access and mapping difficulty. 10 Previous studies have shown that acute and long-term ablation success rates decline with increasing complexity of the underlying anomaly, 5,11 which seems self-evident when the whole spectrum of adult CHD is considered. However, the gap in outcome between simple and complex cases could be narrowed by using newer technologies.…”

Management of the Fontan circulation in the adult patient

“…(45,46) There will be difficulties encountered in EPS in patients with an extra-cardiac conduit Fontan, as there is no direct connection between the venous system and the atrial mass, however there are potential strategies. (47) …”

Is the Extracardiac Conduit the Preferred Fontan Approach for Patients With Univentricular Hearts?

“…Although, to our knowledge, magnetic-guided ablation has yet to be reported for this indication, a retrograde aortic approach has been described for patients with intraatrial conduits. 78 However, this technology is costly, available in a restricted number of centers, and subject to the limited contact force that can be generated. In reality, many older patients with extracardiac Fontans continue to experience intractable arrhythmias and are frequently hospitalized for electric cardioversions, despite various combinations of antiarrhythmic agents.…”