Rare Cardio-Genetic Constellation: Double Inlet Left Ventricle in a Child with Williams–Beuren Syndrome

All articles of this category (opens in new window) Background: Williams–Beuren syndrome (WBS) is a rare genetic multisystem disorder that occurs in 1:7,500 individuals. Several organ systems are affected, such as cardiovascular diseases; a specific craniofacial presentation is noted, and cognitive or behavioral disabilities. Regarding the cardiac malformations, supravalvular aortic stenosis or peripheral pulmonary artery stenosis are the predominant lesions. Methods: We report a case of a child diagnosed prenatally with WBS and an unusual complex cardiac malformation. Fetal echocardiography showed a univentricular anatomy with a double inlet left ventricle (DILV), a hypoplastic outlet chamber, and marked aortic arch hypoplasia. The pulmonary artery arose posterior-rightward in an anteroposterior orientation from the dominant ventricle with diminutive branch pulmonary arteries. In addition, accessory atrioventricular valve tissue caused subvalvar pulmonary obstruction. A fetal MRI revealed no additional noncardiac anomalies. The child was born spontaneously at GW 38 + 4 with a birth weight of 2.3 kg. Immediately after birth, Prostaglandin E1 and an atrioseptostomy led to sufficient hemodynamic improvement. In an interdisciplinary board, surgery was indicated with creation of a Damus–Kaye–Stansel (DKS) anastomosis, reconstruction of the aortic arch, placement of a 3-mm modified Blalock–Taussig-Thomas shunt, together with preservation of an atrial septal defect. Prolonged respiratory weaning and intensified heart failure medication were necessary. Despite all efforts, the patient remained in severe heart failure with persisting systolic and diastolic dysfunction. After repeated interdisciplinary conferences, it was concluded that, given the extremely hypoplastic pulmonary arteries and severely hypoplastic whole thoracoabdominal aorta, no further surgical or interventional options were offered. Discharge was therefore arranged under palliative care. Conclusion: This case illustrates the exceptional diagnostic and therapeutic challenges associated with the coexistence of WBS and DILV. The combination of the severe hypoplasia of the aortic and pulmonic vascular bed, linked to the genetic syndrome, together with complex congenital heart disease, requires an extensive and multidisciplinary diagnostic approach, including detailed imaging, hemodynamic assessment, and genetic evaluation. The decision to refrain from further surgical intervention reflects the delicate balance between the feasibility of surgery and the potential benefit in a genetically determined increased systemic and pulmonary vascular resistance, which finally determines the high risk of morbidity and mortality. Publication History Article published online: 17 February 2026 © 2026. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany