Heart Failure in Infants and Children

Abstract

1. Erin Madriago, MD* 2. Michael Silberbach, MD* 1. *Division of Pediatric Cardiology, Doernbecher Children's Hospital, Oregon Health and Science University, Portland, Ore After completing this article, readers should be able to: 1. Define pediatric heart failure (HF) and review its pathophysiology. 2. Describe the clinical manifestations of pediatric HF. 3. Identify common pediatric HF syndromes. 4. Recognize the differences between pediatric and adult HF. 5. Discuss the treatment of pediatric HF. Pediatric heart failure (HF) is an etiologically diverse disease manifesting a variety of clinical presentations. Nevertheless, in all HF syndromes, whether adult or pediatric, a unifying pathophysiologic mechanism is involved: A cardiac injury (either congenital or acquired) activates both compensatory and deleterious pathways that cause a chronic and progressive course that, if left untreated, ultimately hastens death. Indeed, pediatric HF is the most common reason that infants and children who have heart disease receive medical therapy and accounts for at least 50% of referrals for pediatric heart transplantation. (1) HF results when cardiac output is insufficient to meet the metabolic demands of the body. Over time, decreased cardiac output leads to a cascade of compensatory responses that are aimed directly or indirectly at restoring normal perfusion to the body's organs and tissues. For most adults, HF results from diminished myocardial contractility caused by ischemic heart disease. In contrast, decreased contractile states account for a smaller percentage of causes of pediatric HF. Instead, the various triggers of HF in children can be categorized broadly as syndromes of excessive preload, excessive afterload, abnormal rhythm, or decreased contractility, which all can lead to a final common HF pathway. The overall incidence and prevalence of pediatric HF is unknown, largely because there is no accepted universal classification applied to its many forms. The largest HF burden comes from children born with congenital malformations. It has been estimated that 15% to 25% of children who have structural heart disease develop HF. (2) Although cardiomyopathy is relatively rare, approximately 40% of …