Excluding patent ductus arteriosus of the premature infant, congenital heart disease is estimated to occur in about 0.8% of all children.1 Fortunately, most of these problems are minor or self-limited and do not require intervention. Congenital heart disease requiring intervention is less common—about 3 to 4/1000.2 For this important group of patients with heart disease, the past 70 years have witnessed a remarkable advance in diagnostic and therapeutic techniques such that many of these children with previously lethal defects may now lead relatively normal lives. Congenital heart disease ranks ninth in cause of death of infants <1 year at 2.1 per 100,000 live births in the United States, and is comparable to the death rate for sepsis and respiratory distress syndrome.3
Children with congenital heart disease may be hospitalized at the time of diagnosis if they present with critical heart disease, after cardiac interventions (surgery or transcatheter), or for acute illness related or unrelated to their heart condition. While some congenital cardiac disease has straightforward anatomy, the hospitalist may care for children with the most complex cardiac anatomy, as these children typically spend the most time in hospital. The pediatric hospitalist frequently plays an important role in the care of children with congenital heart disease—especially when it coexists with other disease processes.
While the anatomic variation of congenital heart disease is vast, the four main elements of pathophysiology in congenital heart disease are desaturation, pulmonary overcirculation, pulmonary vascular disease, and compromised systemic perfusion. The interventions we undertake for patients with congenital heart disease are done to address or prevent one or more of these issues. These pathologies are discussed more fully in the context of the more common examples of congenital heart disease.
Congenital heart disease typically presents in one of three time frames: the newborn period, in early infancy, or in childhood. The newborn period usually sees most presentations of critical congenital heart disease. What defines these lesions as “critical” is that survival depends on ductal patency, or emergent surgical or catheter intervention. Typical clues to suggest critical heart disease in the newborn include cyanosis or signs and symptoms of decreased perfusion. Increasingly, newborns with congenital heart disease are born with detailed anatomic diagnoses due to prenatal screening by fetal echocardiography. In some centers, more than half of infants born with serious congenital heart disease have been diagnosed antenatally. Antenatal diagnosis allows for appropriate and anticipatory management of these infants and has led to a measure of improved outcome for complex heart disease.4 One other important presentation for newborns with critical congenital heart disease is the screening program for critical congenital heart disease endorsed by the Centers for Disease Control (CDC) and now adpoted by legislation in over half of the states in the US. This simple screening uses a pulse oximeter to check saturations in the right hand and foot in newborns more than 24 hours old or immediately pre-discharge. Any reading <90%, three readings 90% to 94%, or a more than 3% difference between the hand and the foot triggers the recommendation for a diagnostic echocardiogram. This test will detect most cyanotic congenital heart disease as well as hypoplastic left heart syndrome, and other mixing lesions. A recent meta-analysis of several published studies shows a high sensitivity of this test (76%) for critical congenital heart disease and a low false positive rate (0.05%) when done >24 hours after birth.5