Outcomes of infants and children undergoing surgical repair of ventricular septal defect: a review of the literature and implications for research with an emphasis on pulmonary artery hypertension.

BACKGROUND: Pulmonary vascular disease resulting from CHDs may be the most preventable cause of pulmonary artery hypertension worldwide. Many children in developing countries still do not have access to early closure of clinically significant defects, and the long-term outcomes after corrective surgery remain unclear. Focused on long-term results after isolated ventricular septal defect repair, our review sought to determine the most effective medical therapy for the pre-operative management of elevated left-to-right shunts in patients with an isolated ventricular septal defect. METHODS: We identified articles specific to the surgical repair of isolated ventricular septal defects. Specific parameters included the pathophysiology and pre-operative medical management of pulmonary over-circulation and outcomes. RESULTS: Studies most commonly focused on histologic changes to the pulmonary vasculature and levels of thromboxanes, prostaglandins, nitric oxide, endothelin, and matrix metalloproteinases. Only 2/44 studies mentioned targeted pharmacologic management to any of these systems related to ventricular septal defect repair; no study offered evidence-based guidelines to manage pulmonary over-circulation with ventricular septal defects. Most studies with long-term data indicated a measurable frequency of pulmonary artery hypertension or diminished exercise capacity late after ventricular septal defect repair. CONCLUSION: Long-term pulmonary vascular and respiratory changes can occur in children after ventricular septal defect repair. Research should be directed at providing an evidenced-based approach to the medical management of infants and children with ventricular septal defects (and naturally all CHDs) to minimise consequences of pulmonary artery hypertension, particularly as defect repair may occur late in underprivileged societies.