Simplified Guide to Understanding the Anatomy of Congenital Heart Disease

Congenital heart disease (CHD) is the most common congenital malformation, causing up to 10% of infant deaths and 50% of deaths due to a congenital malformation, while extracardiac congenital anomalies are also present in up to 25% of neonates. Approximately 25% of congenital heart lesions can be considered more complex, and one-third will require intervention during infancy. A thorough understanding of the complete anatomic substrate related to the patient's specific congenital cardiac lesion and resultant hemodynamic pathophysiology is essential for early recognition, diagnosis, and planning of optimal intensive care unit management of critically ill pediatric patients by the pediatric intensivist, both before and after surgical- and/or catheterization-based interventions. A systematic method to diagnose and assess CHD is necessary, as exemplified by the sequential segmental approach for describing the malformed heart. Congenital cardiac lesions can then be divided into four pathophysiologically distinct groups, as detailed in this chapter: congenital heart defects with dominant left-to-right shunt, including anomalous pulmonary venous connections; cyanotic congenital heart disease; obstructive congenital heart disease; and complex congenital heart disease. These are described in some detail, emphasizing the morphologic features and variants that may impact patients' health care in the intensive care setting.