Rapid right ventricular pacing for balloon aortic valvuloplasty: expanding its routine use in neonates and infants.

Abstract

Rapid right ventricular pacing during balloon aortic valvuloplasty is commonly used to achieve balloon stability in children and adults. There is no consensus for the use of the technique in neonates and infants. We sought to review our institutional experience with rapid right ventricular pacing-assisted balloon aortic valvuloplasty across all age groups and evaluate the safety and effectiveness of the technique in the sub-group of neonates and infants <12months. Retrospective study between February, 2011 and February, 2020. A total of 37 patients (Group I: 21 neonates/infants <12months and Group II: 16 children 12 months-16 years) were analysed. Catheter-measured left ventricular to aortic gradient reduced from median of 66 mmHg (with a range from 30 to 125 mmHg) to 14 mmHg (with a range from 5 to 44 mmHg) in Group I and 44 mmHg (with a range from 28 to 93 mmHg) to 18 mmHg (with a range from 2 to 65 mmHg) in Group II (p < 0.001). Procedure and fluoroscopy times were identical in the two groups. Balloon:annulus ratio was 0.94 and 0.88 in Groups I and II, respectively. Freedom from reintervention was 100% for Group I at a median time of 3.2 years and 81% at 2.7 years for Group II. Reinterventions in Group II (3/16 pts) were performed predominantly for complex left ventricular outflow tract stenosis. At follow-up echocardiogram, 45% of patients in Group I had no aortic regurgitation, 30% trace-mild, 20% mild-moderate, and 5% moderate aortic regurgitation, whereas in Group II, 50% of patients had no aortic regurgitation, 32% had mild aortic regurgitation, and 18% mild-moderate aortic regurgitation. Unicuspid valves were only encountered in Group 1 (2/21 pts, 10%) and they were predictive of mild-aortic regurgitation during follow-up (p = 0.003). Ventricular fibrillation occurred in three neonates with suspicion of myocardial ischemia on the pre-procedure echocardiogram. All were successfully defibrillated. Rapid right ventricular pacing can be expanded in neonates and infants to potentially decrease the incidence of aortic regurgitation and reintervention rates, hence avoiding high-risk surgical bail-out procedures for severe aortic regurgitation in the first year of life. Myocardial ischemia may predispose to ventricular dysrhythmias during rapid right ventricular pacing.