Percutaneous Pulmonary Valve Implantation in Humans

TLDR

RVOT reconstruction with valved conduits in childhood often necessitates later reintervention for pulmonary regurgitation or stenosis, leading to the use of percutaneous pulmonary valve implantation. PPVI was performed successfully in 58 patients (median age 16) with various congenital heart defects, assessing mortality, hemodynamic improvement, freedom from explantation, and changes in exercise tolerance. The procedure markedly reduced RV pressure, RVOT gradient, and pulmonary regurgitation, improved MRI‑derived ventricular volumes and exercise capacity, and resulted in no mortality.

Abstract

Right ventricular outflow tract (RVOT) reconstruction with valved conduits in infancy and childhood leads to reintervention for pulmonary regurgitation and stenosis in later life.Patients with pulmonary regurgitation with or without stenosis after repair of congenital heart disease had percutaneous pulmonary valve implantation (PPVI). Mortality, hemodynamic improvement, freedom from explantation, and subjective and objective changes in exercise tolerance were end points. PPVI was performed successfully in 58 patients, 32 male, with a median age of 16 years and median weight of 56 kg. The majority had a variant of tetralogy of Fallot (n=36), or transposition of the great arteries, ventricular septal defect with pulmonary stenosis (n=8). The right ventricular (RV) pressure (64.4+/-17.2 to 50.4+/-14 mm Hg, P<0.001), RVOT gradient (33+/-24.6 to 19.5+/-15.3, P<0.001), and pulmonary regurgitation (PR) (grade 2 of greater before, none greater than grade 2 after, P<0.001) decreased significantly after PPVI. MRI showed significant reduction in PR fraction (21+/-13% versus 3+/-4%, P<0.001) and in RV end-diastolic volume (EDV) (94+/-28 versus 82+/-24 mL.beat(-1).m(-2), P<0.001) and a significant increase in left ventricular EDV (64+/-12 versus 71+/-13 mL.beat(-1).m(-2), P=0.005) and effective RV stroke volume (37+/-7 versus 42+/-9 mL.beat(-1).m(-2), P=0.006) in 28 patients (age 19+/-8 years). A further 16 subjects, on metabolic exercise testing, showed significant improvement in VO2max (26+/-7 versus 29+/-6 mL.kg(-1).min(-1), P<0.001). There was no mortality.PPVI is feasible at low risk, with quantifiable improvement in MRI-defined ventricular parameters and pulmonary regurgitation, and results in subjective and objective improvement in exercise capacity.