Sildenafil for Noncompaction Cardiomyopathy Treatment in a Child: Case Report

Abstract

Congestive heart failure (CHF) occurs when the heart can no longer maintain the baseline metabolic demand triggered by physiological venous pressure. In the pediatric population, it corresponds to a complex entity with multiple etiologies, depending on the age group assessed, being mainly associated with congenital structural malformations, cardiomyopathies, or secondary to arrhythmogenic, infectious, ischemic, toxic or infiltrative events1. The incidence of CHF in children also varies according to the underlying condition, ranging from 15% to 25% in patients with congenital heart defects. In structurally normal hearts, cardiomyopathy is the major factor associated with CHF, with a 40% incidence of CHF reported in those patients1. Isolated noncompaction cardiomyopathy is a rare disease, whose incidence in the general population ranges from 0.014% to 1.3%. It might result from a failure in compaction of the ventricular myocardium between weeks 5 and 8 of the embryonic life, leading to the persistence of myocardial trabeculations and deep recesses, which communicate with the ventricular cavity, generating myocardial thickening in two distinct layers (compacted and noncompacted). Initially reported in the pediatric population or with a congenital cardiopathy, it also affects adults with no other heart disease2,3. This failure in the regression of embryonic sinusoids is postulated to be due to the extremely high pressures that the ventricles undergo in that developmental period. However, the literature has reported a genetic aspect emphasizing the relationship of the disease with different genes, such as the mutation of gene G4.5 in families with severe infantile noncompaction cardiomyopathy, mutations P121L, CYPHER/ZASP, E101K, and a locus containing the disease gene in chromosome 11p153. The major complications of patients with noncompaction cardiomyopathy are pulmonary thromboembolism, arrhythmias and CHF3. In addition to the usual treatment of CHF, new classes of drugs, such as the phosphodiesterase type 5 (PDE-5) inhibitors, have been studied4. They are currently used for the treatment of erectile dysfunction and pulmonary arterial hypertension, and began to be studied for the treatment of CHF after the demonstration of higher PDE-5 expression in myocytes and vascular muscle cells, as well as of markers of oxidative stress in patients with CHF5. We report, for the first time, the clinical and laboratory findings of a patient with noncompaction cardiomyopathy after the addition of sildenafil (PDE-5 inhibitor) to the usual treatment.