Spontaneously Corrected Hypoplastic Left Heart: A Case Report and Exceptional Opportunity to Discuss Etiology with Novel Therapeutic Vision.

Hypoplastic left heart syndrome (HLHS) is a relatively prevalent fetal echocardiography finding in complex congenital heart diseases. Current studies indicate that intrinsic and extrinsic mechanisms could be involved in the development of left heart hypoplasia. Left ventricular inflow or outflow disorders may cause left heart hypoplasia. Prenatal aortic valvuloplasty has become more common as a therapeutic strategy. Our case presentation provides an opportunity for a new vision toward the etiology, prevention, and treatment of HLHS. In our patient, prenatal progressive left heart hypoplasia associated with restrictive foramen oval (FO) suggested the likelihood of a flow-mediated mechanism. Additionally, postnatal improvement of the hypoplastic left heart in the presence of a functional perimembranous ventricular septal defect (PM-VSD) reinforced the suspicion of an extrinsic mechanism. Pre- or postnatal interventional creation of an atrial septal defect (ASD) or VSD is our proposed method for HLHS in selected patients.