Miocardiopatia não compactada em crianças e adolescentes: do desafio do diagnóstico ecocardiográfico ao acompanhamento clínico / Non-compacted cardiomyopathy in children and adolescents: from the challenge of echocardiographic diagnosis to clinical follow-up

Fundamentos: Miocardiopatia não compactada (MCNC) caracteriza-se por hipertrabeculações e recessos profundos no ventrículo esquerdo, com apresentação clínica heterogênea, desde pacientes assintomáticos a insuficiência cardíaca (IC), eventos tromboembólicos arritmias com risco de morte súbita. Por ser rara e não apresentar critérios diagnósticos bem definidos, sua história natural na pediatria é pouco conhecida. Este estudo descreve a apresentação e evolução clínica de pacientes portadores de MCNC. Metodologia: Estudo observacional, longitudinal, prospectivo, de pacientes pediátricos atendidos em um centro de referência em cardiologia pediátrica provenientes da região metropolitana II do Estado do Rio de Janeiro, com fenótipo de MCNC ao ecocardiograma (ECO) no período de 2 anos de acompanhamento, provenientes do Registro ChARisMa. Resultados: Analisados seis pacientes com MCNC, de 4 a 14 anos de idade, média de idade de 7,5 anos (DP: 3,93), 3 do sexo masculino (50%). Apresentando-se com IC (n=2), sopro cardíaco (n=1), arritmia cardíaca (n=1), assintomático (n=1) ou em investigação de síndrome genética (n=1). Fenótipos ao ECO: MCNC/Miocardiopatia dilatada (n=1) e MCNC/Miocardiopatia restritiva (n=1), fenótipo isolado de MCNC (n=4). A ressonância magnética cardíaca foi realizada, confirmando o diagnóstico (n=4). Os desfechos observados foram tromboembolismo, indicação de transplante cardíaco e taquicardia ventricular sustentada. Conclusões: Esta série de casos proporciona dados relevantes da MCNC pediátrica, mostrando a heterogeneidade da apresentação clínica, bem como a ocorrência de complicações potencialmente fatais. São necessários mais estudos prospectivos para que seu diagnóstico seja corretamente realizado e sua evolução clínica, resposta terapêutica e prognóstico sejam mais bem conhecidos. (AU)

Background: Non-compacted cardiomyopathy (NCCM) is characterized by hypertrabeculations and deep recesses in the left ventricle, with a heterogeneous clinical presentation, ranging from asymptomatic patients to those with heart failure (HF), thromboembolic events and arrhythmias with risk of sudden death. As it is rare and does not have well-defined diagnostic criteria, its natural history in pediatrics is poorly understood. This study describes the clinical presentation and clinical course of patients with NCCM. Methodology: Observational, longitudinal, prospective study of pediatric patients seen at a pediatric cardiology referral center from metropolitan region II in the state of Rio de Janeiro, with NCCM phenotype on echocardiogram (ECHO) during a 2-year follow-up, from the ChARisMa registry. Results: 6 patients aged 4 to 14, with NCCM, were analyzed. Mean age 7.5 years (SD: 3.93), 3 males (50%). The patients presented HF (n=2), cardiac murmur (n=1), cardiac arrhythmia (n=1), were asymptomatic (n=1) or were under investigation for a genetic syndrome (n=1). Phenotypes on ECHO: NCCM/dilated cardiomyopathy (n=1) and NCCM/restrictive cardiomyopathy (n=1), isolated phenotype of NCCM (n=4). Cardiac magnetic resonance imaging was performed and confirmed the diagnosis (n=4). The outcomes observed were thromboembolism, indication for heart transplantation, and sustained ventricular tachycardia. Conclusions:This case series provides relevant data for pediatric NCCM as it shows its heterogeneous clinical presentation and potentially fatal complications. More prospective studies are needed for an accurate diagnosis and to allow its clinical course, therapeutic response and prognosis to be better known. (AU)

[Noncompaction cardiomyopathy]. / "Non-compaction"-Kardiomyopathie.

Noncompaction cardiomyopathy (NCCM) is a genetic myocardial disorder, which is characterized by a two-layered ventricle wall with a thin compact outer layer and a noncompacted inner layer, with prominent trabeculations and deep intratrabecular recesses communicating with the ventricle cavity without any contact to the coronary system. Before the initial description as isolated left ventricle cardiomyopathy (ILVCN) in 1984 by Engberding and Bender, the morphological characteristics had been described only in association with other congenital cardiac disorders, such as atresia of the semilunar valves. The disease usually involves the myocardium of the left ventricle but involvement of the right ventricular has recently been shown. Due to delayed diagnosis and therapy, in advanced stages NCCM can result in heart failure. Life-threatening complications, such as malignant arrhythmia with sudden cardiac death and embolic events have been observed in patients with NCCM. A multimodal investigation including echocardiography and cardiac magnet resonance tomography (CMR) as well as a focused analysis of symptoms can allow a valid diagnosis.

Left ventricular non-compaction cardiomyopathy.

Left ventricular non-compaction, the most recently classified form of cardiomyopathy, is characterised by abnormal trabeculations in the left ventricle, most frequently at the apex. It can be associated with left ventricular dilation or hypertrophy, systolic or diastolic dysfunction, or both, or various forms of congenital heart disease. Affected individuals are at risk of left or right ventricular failure, or both. Heart failure symptoms can be induced by exercise or be persistent at rest, but many patients are asymptomatic. Patients on chronic treatment for compensated heart failure sometimes present acutely with decompensated heart failure. Other life-threatening risks of left ventricular non-compaction are ventricular arrhythmias or complete atrioventricular block, presenting clinically as syncope, and sudden death. Genetic inheritance arises in at least 30-50% of patients, and several genes that cause left ventricular non-compaction have been identified. These genes seem generally to encode sarcomeric (contractile apparatus) or cytoskeletal proteins, although, in the case of left ventricular non-compaction with congenital heart disease, disturbance of the NOTCH signalling pathway seems part of a final common pathway for this form of the disease. Disrupted mitochondrial function and metabolic abnormalities have a causal role too. Treatments focus on improvement of cardiac efficiency and reduction of mechanical stress in patients with systolic dysfunction. Further, treatment of arrhythmia and implantation of an automatic implantable cardioverter-defibrillator for prevention of sudden death are mainstays of therapy when deemed necessary and appropriate. Patients with left ventricular non-compaction and congenital heart disease often need surgical or catheter-based interventions. Despite progress in diagnosis and treatment in the past 10 years, understanding of the disorder and outcomes need to be improved.

Left ventricular noncompaction.

Left Ventricular Noncompaction (LVNC) is a genetic cardiac disease of emerging importance with a distinct clinical and pathophysiological presentation. The most common clinical manifestations include heart failure, arrhythmias and embolic events, and in children it may be associated with facial dysmorphisms and Wolff-Parkinson-White syndrome. The diagnosis of LVNC, however, is often missed, most often as a consequence of ignorance of the condition. Echocardiography is considered the reference standard for the diagnosis of LVNC. Prognosis remains poor for patients with impaired systolic left ventricular function, as treatment options are very limited. Because of the familial association of LVNC, first-degree relatives should be screened by Echocardiography.