Use of the advisor™ HD Grid mapping catheter in transcatheter ablation of atrial arrhythmias in palliated CHD and children without CHD.

OBJECTIVE: In this study, we describe our experience utilising Advisor™ High Density (HD) Grid mapping catheter in transcatheter ablation of intraatrial re-entrant and focal atrial tachycardias with or without CHD. METHODS: Forty-five consecutive patients with intraatrial re-entrant and focal atrial tachycardia who underwent a transcatheter ablation procedure by using Advisor™ HD Grid mapping catheter and high-density mapping system in our hospital from January 2017 to January 2023 were included into the study. RESULTS: The mean age of the patients was 14.2 ± 7.3 years (6-32 years), and the mean weight was 48.3 ± 16.2 kg (22-83 kg). Of the total 45 patients, 21 were intraatrial re-entrant tachycardia and 25 were focal atrial tachycardia. Of the 21 re-entrant circuits, 15 were classified as cavotricuspid isthmus-dependent and 5 were non-cavotricuspid isthmus-dependent. In one patient, two re-entrant circuits were identified. A transbaffle ablation was successfully performed from the left atrium in one patient. Of the 25 focal atrial tachycardia, 19 were from right atrium and 6 were from left atrium. A cryoablation was performed in only one patient and radiofrequency ablation in others. The mean procedure time was 180 ± 64 minutes. The mean follow-up period was 69.3 ± 35.3 months. Acute success was 95.5%. Recurrence was noted in two patients (4.4%). CONCLUSION: Advisor™ HD Grid mapping catheter was found to be safe and achieved an acceptable success in transcatheter ablation of patients with intraatrial re-entrant tachycardia and focal atrial tachycardias.

Experience of left ventricular outflow tract arrhythmia ablation in paediatric patients using limited fluoroscopy and three-dimensional mapping technique.

OBJECTIVE: The left ventricular outflow tract is an important source of ventricular arrhythmias. Up to one-third of all idiopathic ventricular arrhythmias in patients with structurally normal hearts may arise from this region. We would like to share the results of our left ventricular outflow tract ablation using three-dimensional mapping and limited fluoroscopy. MATERIALS AND METHODS: This is a single-centre retrospective cohort study. Forty-six consecutive patients who underwent left ventricular outflow tract ablation procedures between January 2015 and June 2023 were included in the study. The EnSite Precision System (Abbott, St. Paul, MN, USA) was used to facilitate mapping and to reduce or eliminate the need for fluoroscopy. RESULTS: The study group comprised 29 males and 17 females, with a mean age of 13.4 ± 4.5 years. The most common location for arrhythmias was the left coronary cusp (n : 21). Other locations, in sequence, included the junction of the right and left coronary commissure (n : 10), right coronary cusp (n : 10), left ventricular outflow tract endocardium (n:4), aorto-mitral junction (n : 1), and great cardiac vein (n : 1). Nine of these patients had previously undergone unsuccessful right ventricular outflow tract ablation at another centre. Cryoablation was performed in three patients, irrigated radiofrequency ablation in three patients, and conventional radiofrequency ablation in the remaining patients. The acute success rate was 100%, and no recurrences were observed. The mean follow-up period was 49.6 ± 24.4 months. All patients were asymptomatic and were being followed without antiarrhythmic medication. CONCLUSION: Although left ventricular outflow tract ablations pose a risk for coronary artery and heart valve complications, they can be performed successfully and safely with the guidance of three-dimensional mapping.

A Challenging Interventional Procedure: Transcatheter Closure of Tubular Patent Ductus Arteriosus in Patients with Pulmonary Hypertension.

Transcatheter closure of the tubular ducts remains the most challenging procedure, with higher complication rates than other types. This study evaluates the characteristics of transcatheter closure of tubular ducts with pulmonary hypertension. 73 patients with tubular ducts who underwent cardiac catheterization for transcatheter PDA closure were analyzed. The mean age and weight were 1.93 ± 2.68 years and 8.83 ± 6.14 kg, respectively. Transcatheter closure was attempted in 72 patients. Four cases (5.5%) were referred to surgery, while the procedure was completed in the remaining (94.5%). Amplatzer duct occluder (ADO) I or Cardiofix duct occluder (CDO) was the most commonly used devices. However, the use of Amplatzer vascular plug (AVP) II raised in recent years. The most common concern was aortic protrusion/stenosis in ADO I/CDO devices, but most regressed during follow-up. Iatrogenic coarctation of the aorta was observed in two with ADO I/CDO. Embolization of the device to the pulmonary artery was observed in three with CDO, AVP II, and AVP I. Significant left pulmonary artery stenosis requiring stenting developed in one after closure with an MVSDO device. Tubular ducts are highly associated with pulmonary arterial hypertension, and transcatheter closure of them is still challenging despite the developing device armamentarium. Although ADO I or similar devices are widely used, off-label devices are usually needed at increasing rates. The AVP II device is unsuitable for short tubular ducts but seems the best option for long ones.