- Initiate stabilization of airway, breathing, and circulation (ABC).
- Place the patient on the monitor, obtain a full set of vitals, and establish intravenous (IV) access.
- The initial clinical evaluation should focus on volume status and evaluate venous congestions, signs of edema, hepatomegaly, and anterior fontanelle (if present).
Heart failure (HF) is a clinical syndrome with reduced cardiac output, increased venous pressures, and cellular changes that cause progressive deterioration of the failing heart and premature myocardial cell death.
In the United States, the incidence of pediatric HF is 0.9-7.4 per 100 000. Incidence of pediatric HF related hospitalization is 11 000-14 000 annually. In-hospital mortality rates range from 7%-26%.
In HF, the heart is not able to supply adequate blood to the tissues to meet metabolic demands. A primary insult can be secondary to ischemia, infection, or tachycardia. This causes a response cascade to preserve blood flow to vital organs.
In a state of poor systemic perfusion, reduced baroreceptor stimulation activates the sympathetic nervous system and releases norepinephrine and epinephrine. This improves heart rate, cardiac contractility, and vasoconstriction, causing increases in preload and afterload. However, young children have poor abilities to increase stroke volume through the Frank-Starling curve; this leads to profound tachycardia to maintain contractility and thus cardiac output.
Decreased renal blood flow activates the renin angiotensin aldosterone system (RAAS) and causes an increase in sodium and fluid retention, as well as release of arginine vasopressin. These mechanisms further increase preload.
A volume-overloaded state stimulates cardiac wall stretch, which activates cardiomyocyte production of brain natriuretic peptide (BNP) and atrial natriuretic peptide (ANP). The natriuretic peptide system counteracts RAAS by reducing renin secretion and aldosterone production. It also causes vasorelaxation, natriuresis, and diuresis. Elevated plasma levels of BNP positively correlate with disease severity.
Due to the activation of these pathways, patients retain fluid in their lungs, abdomen, and extremities, leading to symptoms of fatigue, peripheral edema, and shortness of breath.
Etiology of HF has demonstrated worldwide variation by income, with respiratory tract infections and severe anemia predominating in lower income countries, and congenital heart disease (CHD) and cardiomyopathies in higher income countries. The leading cause of pediatric HF in the United States in infants is CHD; in older children, the leading cause of HF is cardiomyopathies. Infants account for 64% of all HF admissions due to the primary cardiac diagnosis for HF entailing CHD (69%).
The estimated birth prevalence of CHD in North America is estimated to be 6.9/1000 births. Approximately 33% of CHD and 57%-83% of critical lesions are diagnosed in the newborn period prior to discharge. The remainder of these infants may potentially present to the emergency department (ED) as in shock, cyanotic, or with congestive HF.
The second leading cause of pediatric HF is cardiomyopathy (13%-14%). The remainder of cases are due to arrhythmia (12%-15%), and, lastly, myocarditis (2%). Dilated cardiomyopathy has an incidence of 0.57 per 100 000 persons.
Neonates with CHD who are ductal dependent for pulmonary or systemic circulation present in shock or cyanosis as the ductus arteriosus closes in the first 1-2 weeks of life. Hypoplastic left heart syndrome presents on days 3-7 of life. Severe coarctation presents on days 7-10 of life.
Lesions that result in pulmonary overcirculation present in the first 2-3 months of life as lower pulmonary vascular resistance increases left to right shunting, leading to pulmonary edema. A ventricular septal defect (VSD) or atrial-ventricular septal defect (AVSD) presents in months 1-3 of life.
Less common etiologies include infectious and inflammatory diseases, oncologic processes, metabolic syndromes, renal failure (acute, chronic), and malnutrition. HF can be due to overcirculation, as seen in CHD and valve disease, or pump failure, occurring in myocarditis, pericarditis, toxins, arrhythmias, and cardiomyopathies.
Classical symptoms of acute congestive HF include a gallop on auscultation, hepatomegaly, poor pulses, tachypnea, and jugular venous distention (JVD). Unfortunately, pediatric patients do not typically present in this manner and lack symptoms of JVD and peripheral edema. Infants present with feeding difficulties, sweating with feeds, fussiness, failure to thrive, sinus tachycardia, cyanosis, and tachypnea. Young children present with abdominal pain, nausea / vomiting, chest pain, wheezing, fatigue, and exercise intolerance, and older children present with shortness of breath.
The presentation of myocarditis as an etiology ranges from mild influenza-like symptoms to respiratory distress, HF, and shock. Myocarditis is an inflammatory disease of the myocardium that can lead to nonischemic dilated cardiomyopathy and subsequent HF.
Pericarditis presents as fever with chest pain. Patients must be evaluated for complications of effusion and cardiac tamponade.
Secondary Causes of Heart Failure:
- Neonates with cyanotic lesions, CHD – Etiology includes transposition of great arteries (TGA), tetralogy of Fallot (ToF), tricuspid atresia, truncus arteriosus, and total anomalous pulmonary venous return (TAPVR) with obstructed veins. Presenting signs and symptoms include cyanosis and increased fussiness.
- Neonates with ductal-dependent CHD, presenting as patent ductus arteriosus (PDA) closes – Etiology includes critical aortic stenosis, coarctation of aorta, obstructed TAPVR, TGA with intact ventricular septum, hypoplastic left heart syndrome (HLHS), and anomalous left coronary artery from the pulmonary artery (ALCAPA) with myocardial infarction (MI). Patients may be in shock with poor feeding, fussiness, and lethargy.
- Neonates (4-8 weeks of life) with left-to-right shunts presenting as PVR drops, causing overcirculation – Etiology includes ventricular septal defect (VSD), PDA, AV canal defect, partial anomalous pulmonary venous return (PAPVR), and ALCAPA with recurrent ischemia and cardiac failure. Look for CHF, feeding difficulty, sweating with feeds, failure to thrive, difficulty breathing, and fussiness. Signs are tachypnea with labored breathing, rales, hepatomegaly, and cyanosis.
- School-aged children and adolescents – Etiology includes atrial septal defect (ASD), cardiomyopathy, myocarditis, pericarditis, Kawasaki disease, autoimmune or rheumatic valvular disease, and neuromuscular disorders. Look for respiratory or gastrointestinal (GI) symptoms and fever with chest pain.