Hypoplastic left heart syndrome (HLHS) is a major form of congenital heart disease, with universal mortality if left untreated. Even with treatment, survival to eventual palliative univentricular Fontan circulation is in the order of 65% at the age of 5 years. The condition also carries with it a significant load in terms of comorbidities, recurrent interventions, and reduced quality of life. Fetal diagnosis of HLHS is important for accurately counselling the prospective parents on the available options during and after the pregnancy. It is crucial for the adequate planning of, and preparation for, delivery, with evidence emerging that babies delivered with such preparation are in better preoperative condition. Risk stratification is possible with the assessment of restrictive flow at the interatrial septum and the use of magnetic resonance imaging to assess the status of the fetal lungs in this situation. Fetal intervention in cases of a restrictive atrial septum is an emerging and challenging area, with limited evidence for efficacy currently. Due to the high-risk nature of this condition, it is difficult to prove that fetal diagnosis makes any significant impact on mortality.
Improved Surgical Outcome After Fetal Diagnosis of Hypoplastic Left Heart Syndrome