In neonates, congestive heart failure (CHF) secondary to congenital heart lesions predominates, with primary cardiac functional abnormalities (eg, dilated cardiomyopathy, myocarditis) relatively rare. When present, primary myocardial disease is associated with decreased intrinsic cardiac function and cardiac output, leading to tachycardia, diaphoresis, fluid overload, pulmonary congestion (secondary to increased left-sided filling pressures), feeding intolerance, ischemic injury of the brain and other end organs, and eventually death.1 In contrast, in patients with heart failure secondary to congenital heart disease, several mechanistic pathways and modes of presentation exist. In left ventricular (LV) obstructive lesions (eg, critical aortic stenosis), severely increased afterload depresses apparent cardiac function even if the muscle itself is normal. In severe forms in which subendocardial fibrosis is present, cardiac contractility may be truly reduced. In patients with left-to-right shunts, intrinsic cardiac contractile function is either normal or enhanced, and cardiac output is usually well preserved until the late stages of disease. Increased (and inefficient) cardiac work results in typical heart failure symptoms as described, with end-stage heart failure manifesting as reduced end-organ perfusion secondary to selective vasoconstriction, cardiovascular collapse, and death.
The symptoms of CHF and its root causes must be recognized quickly and appropriate therapy initiated. Strategies for management of CHF in the neonate are largely similar based on whether the etiology is congenital heart disease or a primary myocardial disorder; however, there are some key differences. Thus, management of these patients should always involve consultation with a pediatric cardiologist.
In the newborn population, the age at presentation can provide clues regarding the most likely etiology (Table 81-1). Signs and symptoms of CHF in the neonate are summarized in Table 81-2. Heart failure, especially that associated with left-sided obstructive lesions, can present dramatically. However, in other conditions, it often presents insidiously. Generalized constitutional symptoms are common, and even with substantially reduced ventricular function, the neonate with CHF may demonstrate little more than failure to thrive, irritability, or unexplained tachycardia. If cardiac output is inadequate, peripheral vasoconstriction, arrhythmia, and deteriorations in laboratory indices of renal and hepatic function may develop. This condition, termed cardiogenic shock, requires urgent treatment before irreversible end-organ dysfunction occurs.
Table 81-1Heart Failure Presenting in the Neonate by Age at Presentation |Favorite Table|Download (.pdf) Table 81-1Heart Failure Presenting in the Neonate by Age at Presentation
Heart failure that presents at birth:
Persistent pulmonary hypertension of the newborn
Total anomalous pulmonary venous return with obstruction
Ebstein anomaly of the tricuspid valve (large heart and cyanosis)
Myocarditis acquired in utero
Arrhythmias (fetal heart block, supraventricular tachycardia)
Complete heart block secondary to maternal anti-SSA/Ro or anti-SSB/La antibodies
Arterio-venous malformations (AVMs), often cerebral
Heart failure that presents in the first week of life (LV outflow tract obstructions):
Coarctation of the aorta
Critical aortic stenosis
Mitral stenosis (often part of Shone ...