How to perform transconduit and transbaffle puncture in patients who have previously undergone the Fontan or Mustard operation

Atrial Transseptal Catheterisation: Challenging Scenarios and Techniques to Overcome Them

Atrial transseptal catheterisation is a fundamental skill of any interventional electrophysiologist. In this review, various scenarios that pose unique challenges to atrial transseptal catheterisation are discussed. These scenarios include post-surgical or congenital malformations of the interatrial septum, presence of interatrial septal closure devices, absent or obstructed inferior vena cava and complex congenital heart disease after palliative surgery. Transseptal catheterisation in all of the above situations is feasible and can be performed safely with the aid of dedicated tools and specific techniques.

Fluoroscopy-free ablation in congenital heart disease of moderate or great complexity

BACKGROUND

Fluoroscopy-free (FF) ablation has been demonstrated to be safe and successful in patients with structurally normal hearts, but has not been systematically evaluated in patients with congenital heart disease (CHD) of moderate or great (M/G) complexity. This study aimed to evaluate and compare feasibility, safety, and outcomes of FF ablation in patients with or without M/G-CHD.

METHODS

Consecutive patients undergoing electrophysiologic study and intended catheter ablation over a 24-month period were included. Subgroups were created based on presence and complexity of CHD-M/G-CHD or simple complexity/no CHD (S/N-CHD). Cases with total radiation dose of zero qualified as FF. Demographic and peri-procedural variables and outcome data were analyzed.

RESULTS

A total of 89 procedures were included with 62 comprising the S/N-CHD group and 27 comprising the M/G-CHD group. Of the M/G-CHD patients, 13 had CHD of great complexity (including 6 single ventricle/Fontan and 2 atrial switch patients). Patients with M/G-CHD were older, had higher BMI, had higher incidence of ventricular dysfunction, and greater incidence of complex arrhythmias. Fluoroscopy-free ablation was achieved in 59% of M/G-CHD and 69% of S/N-CHD patients. Both groups had similar rates of acute procedural success, recurrence, and complications. Fluoroscopy was primarily used to visualize pre-existing transvenous leads and peripheral venous anomalies or to guide transbaffle/transseptal puncture.

CONCLUSIONS

A fluoroscopy-free ablation approach is feasible, safe, and successful even in patients with M/G-CHD with comparable outcomes to those with S/N-CHD.

New developments in catheter ablation for patients with congenital heart disease

Introduction: There are numerous challenges to catheter ablation in patients with congenital heart disease (CHD), including access to cardiac chambers, distorted anatomies, displaced conduction systems, multiple and/or complex arrhythmia substrates, and excessively thickened walls, or interposed material. Areas covered: Herein, we review recent developments in catheter ablation strategies for patients with CHD that are helpful in addressing these challenges. Expert opinion: Remote magnetic navigation overcomes many challenges associated with vascular obstructions, chamber access, and catheter contact. Patients with CHD may benefit from a range of ablation catheter technologies, including irrigated-tip and contact-force radiofrequency ablation and focal and balloon cryoablation. High-density mapping, along with advances in multipolar catheters and interpolation algorithms, is contributing to new mechanistic insights into complex arrhythmias. Ripple mapping allows the activation wave front to be tracked visually without prior assignment of local activation times or window of interest, and without interpolations of unmapped regions. There is growing interest in measuring conduction velocities to identify arrhythmogenic substrates. Noninvasive mapping with a multielectrode-embedded vest allows prolonged bedside monitoring, which is of particular interest in those with non-sustained or multiple arrhythmias. Further studies are required to assess the role of radiofrequency needle catheters and stereotactic radiotherapy in patients with CHD.

Guidewire pacing during transcatheter aortic valve implantation in a patient with complex congenital heart disease

We present a case of temporary guidewire pacing in a patient with Fontan anatomy during transcatheter aortic valve implantation. Temporary pacing was successfully achieved utilizing this method without complications. There is an increasing population of patients with complex congenital heart disease and expanding variety of transcatheter interventions. Due to limitations in vascular access and surgical anatomies, guidewire pacing may have a wide array of potential applications in pediatrics and the congenital heart disease population.

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.

Evasion maneuver for transseptal approach during cryoballoon pulmonary vein isolation

Purpose

Pulmonary vein isolation (PVI) is a cornerstone therapy in patients with symptomatic atrial fibrillation. One current method is performing a PVI using a cryoballoon (CB). The CB is inserted into the left atrium via a steerable sheath. However, at times, passing of the interatrial septum by the sheath is hindered, e.g., due to septal fibrosis. Here we report our experience with an evasion maneuver to facilitate this approach using a 6F multipolar and steerable coronary Sinus catheter (CS) for predilatation of the interatrial septum.

Methods and results

We report 10 patients undergoing a CB-PVI, where the investigator experienced difficulties in passing the interatrial septum with the CB sheath. In these cases, after three conventional abortive attempts, we predilated the transseptal puncture site using both the CS catheter and the dilatator of the CB sheath. Thereafter access of the CB sheath to the left atrium could be achieved instantly and without further resistance.

Conclusion

We report a safe and feasible maneuver to facilitate transseptal access with the CB steerable sheath in cases complicated by excessive interatrial resistance.