Children born with the major congenital heart defect hypoplastic left heart syndrome (HLHS) often must undergo a series of corrective surgeries beginning at birth. While most have the standard three-stage Norwood procedure, a hybrid strategy has been introduced to offset some disadvantages associated with the Norwood surgeries. In a report in The Journal of Thoracic and Cardiovascular Surgery, investigators compare whether outcomes can be improved if an arterial shunt is used as a source of pulmonary blood flow rather than the more conventional venous shunt as part of the hybrid strategy of HLHS surgical reconstruction.
For children born with life-threating hypoplastic left heart syndrome (HLHS), reconstructive surgeries can restore blood circulation. While the most common corrective approach is the three-stage Norwood procedure, an alternative strategy, hybrid palliation, allows deferral of the more complex reconstructions to when the child is somewhat older and better able to successfully recover from major surgery. A report in The Journal of Thoracic and Cardiovascular Surgery, the official publication of the American Association for Thoracic Surgery (AATS), evaluates whether an arterial shunt in the hybrid palliation may be a better source for the pulmonary blood supply than the more frequently used venous shunt.
Each year, almost 1000 babies in the United States are born with HLHS, a congenital condition in which the left side of the heart is undeveloped and systemic blood flow is inadequate to sustain life. Without surgical intervention, either reconstruction of structures of the heart and blood vessels or cardiac transplantation, HLHS is fatal. Symptoms of HLHS manifest hours or days after birth, when the ductus arteriosus, a blood vessel connecting the pulmonary artery and the aorta, begins to close. Symptoms include breathing problems, pounding heart, weak pulse, ashen or bluish skin, and heart murmurs. The three-stage Norwood procedure occurs at different times of development, with Norwood Stage I typically performed soon after birth, Norwood II (commonly referred to as a bidirectional Glenn – or cavopulmonary – shunt) between 4 and 6 months of age, and the final surgery, termed a modified Fontan Procedure, between 2 and 5 years of age.
Although Norwood palliation has achieved 30-day survival rates of 90% or more, surgeons strive for better ways to improve outcomes for the highest risk patients. “Hybrid palliation was initially thought to be a therapy that would eventually supplant standard Norwood palliation because of its technical simplicity, its avoidance of cardiopulmonary bypass (open heart surgery) and prolonged perioperative recovery in the neonatal period, and an intuitive notion that it would be associated with improved neurodevelopmental outcomes,” commented David M. Overman, MD, Chief of the Division of Cardiovascular Surgery at the Children’s Hospitals and Clinics of Minnesota (Minneapolis) in an accompanying editorial.