Decreased Incidence of Right-Ventricular Outflow Tract Complications Using a Retrograde Snare Technique for Radiofrequency Pulmonary Valve Perforation

Abstract

Perforation of the atretic pulmonary valve with balloon dilation in infants with pulmonary atresia with intact ventricular septum (PA-IVS) is standard initial therapy for right-ventricular (RV) decompression. This procedure often results in adequate pulmonary blood flow, thus eliminating the need for neonatal surgery. Nonetheless, the incidence of RV outflow-tract complications and mortality for this intervention is significant. We report our experience with retrograde snare-guided radiofrequency (RF) perforation in an attempt to improve accuracy and decrease procedural complications. Medical records were reviewed for the period between March 2007 and May 2010 for all patients with PA-IVS who presented to the catheterization laboratory for attempted RF perforation in infancy. Specific details reviewed included demographics, preprocedural echocardiographic (echo) data, procedural technique and complications, pre- and post-RV pressures and pulmonary valve gradients, need for surgical intervention in the neonatal period, and short- to medium-term follow-up. Eleven neonates with PA-IVS underwent RF perforation using a retrograde snare-guided technique during the study period. The pulmonary valve was successfully perforated and the wire snared in all 11 patients. Six of 11 atretic valves were crossed on the first attempt with low energy (5 W × 2 s). No episodes of tamponade or RV/PA perforation occurred as confirmed by echocardiogram performed immediately after the procedure. There was no ductal spasm with retrograde catheter manipulations. Sequential dilation of the perforated valve was not necessary. RV pressures decreased from 169 % systemic before dilation to 93 % after dilation (p < 0.001) with a residual pulmonary valve gradient of 16 ± 6 mm Hg. Eight of 11 patients (73 %) were discharged without surgery at an average 16 days after the intervention. Three patients required Blalock-Taussig shunts to augment pulmonary blood flow. Femoral artery thrombus occurred in 4 of 11 patients treated with anticoagulation, and 2 patients had atrial arrhythmias during the procedure. No other complications occurred. No preprocedural echo parameters predicted requirement for surgical shunt before hospital discharge. Retrograde snare-guided pulmonary valve perforation in infants with PA-IVS is safe and may decrease the incidence of significant procedural complications.