Single-stage reconstruction of supravalvular aortic stenosis and severe peripheral pulmonary artery stenosis in an infant with Williams syndrome: a case report

Abstract

Williams syndrome (WS) is a rare multisystem disorder caused by a 7q11.23 microdeletion, leading to elastin deficiency and generalized arteriopathy. The most clinically significant manifestations include supravalvular aortic stenosis (SVAS) and peripheral pulmonary artery stenosis (PPAS). Severe, multilevel PPAS in early infancy presents a major surgical challenge due to near-systemic right ventricular (RV) pressures and the technical demands of reconstructing small-caliber vessels in low-body-weight patients.
Case presentation. We report a 3-month-old infant (4.9 kg) with WS presenting with severe bilateral PPAS and SVAS. Preoperative cardiac catheterization demonstrated an RV-to-aortic (RV/Ao) pressure ratio of 0.95 (RV systolic pressure 95 mm Hg). Single-stage surgical correction was performed via median sternotomy: Doty aortoplasty for SVAS and extensive bilateral patch augmentation of the main, branch, and lobar pulmonary arteries using autologous pericardium. The postoperative course was complicated by reperfusion syndrome, hemodynamic instability, and transient acute renal failure requiring peritoneal dialysis. Despite these challenges, the patient recovered fully. At 6-month follow-up catheterization, RV systolic pressure had decreased to 30 mm Hg (RV/Ao ratio 0.30), with sustained hemodynamic improvement.
Conclusions. Early single-stage reconstruction of combined SVAS and multilevel PPAS is feasible and can provide excellent, durable relief of RV pressure overload in small infants with Williams syndrome, even in the presence of complex vascular anatomy and significant early postoperative morbidity. This approach warrants consideration in selected high-risk cases.