Comparative transcatheter intervention for pulmonary valve stenosis: multicenter collaborative study across pediatric and veterinary cardiology centers

Introduction/objectives: Transcatheter therapeutics have revolutionized treatment of pulmonary valve stenosis (PS). Further understanding of PS intervention may help improve outcomes for different species. This study describes characteristics and immediate outcomes in children and dogs undergoing balloon pulmonary valvuloplasty (BPV) or transpulmonary stent implantation for congenital PS. Animals, materials, and methods: Multicenter, retrospective review from 2 pediatric and 3 veterinary centers. Demographics, procedural characteristics, and outcomes were assessed. Successful intervention was defined as a 50% reduction in transvalvar pulmonary pressure gradient (PG) within 24 h or final invasive transpulmonary gradient <40 mmHg. Results: Data (78 children; 165 dogs) from July 2019 to June 2021 were included with BPV performed in 77 children and 145 dogs, and stent implantation in one child and 20 dogs. Stenosis was valvar in 64 children (82%) and 141 dogs (86%; P=0.50). Mean (SD) initial echocardiographic peak PG was higher in dogs [122 mmHg (39) vs. 70 mmHg (22)]. More dogs received beta-blockade at intervention (92% vs. 3%). Congestive heart failure was evident in 14% of dogs but no children. Pulmonary valve annulus diameter and balloon:annulus ratio were smaller in children 8.7 mm (3.4); 1.19 (0.3) vs. dogs 12.6 mm (4.2); 1.28 (0.24). Successful transcatheter intervention was achieved in 84% of dogs and 96% of children (P=0.008). Conclusions: Valvar PS occurs in both children and dogs, although lesions might not be completely comparable. Preprocedural PG is higher and beta-blockers are more commonly prescribed in dogs. Successful transpulmonary intervention can be achieved in most pediatric and canine patients.