Segmental cardiac strain assessment by two-dimensional speckle-tracking echocardiography in surviving MIS-c patients: Correlations with myocardial flow reserve (MFR) by 13 N-ammonia PET-CT.

BACKGROUND: Multisystem inflammatory syndrome in children (MIS-c) is associated with severe cardiovascular impairment and eventually death. Pathophysiological mechanisms involved in myocardial injury were scarcely investigated, and cardiovascular outcomes are uncertain. Autopsy studies suggested that microvascular dysfunction may be relevant to LV impairment. OBJECTIVE: We aimed to evaluate segmental LV longitudinal strain by 2DST echocardiography and myocardial flow reserve (MFR) by 13 N-ammonia PET-CT, in six surviving MIS-c patients. METHODS: Each patient generated 34 LV segments for combined 2DST and MRF analysis. MFR was considered abnormal when <2, borderline when between 2 and 2.5 and normal when >2.5. RESULTS: From July 2020 to February 2021, six patients were admitted with MIS-c: three males, aged 9.3 (6.6-15.7) years. Time from admission to the follow-up visit was 6.05 (2-10.3) months. Although all patients were asymptomatic and LV EF was ≥55%, 43/102 (42.1%) LV segments showed MFR <2.5. There was a modest positive correlation between segmental peak systolic longitudinal strain and MFR: r = .36, p = .03 for basal segments; r = .41, p = .022 for mid segments; r = .42, p = .021 for apical segments. Median peak systolic longitudinal strain was different among MRF categories: 18% (12%-24%) for abnormal, 18.5% (11%-35%) for borderline, and 21% (12%-32%) for normal MFR (p = .006). CONCLUSION: We provided preliminary evidence that surviving MIS-c patients may present subclinical impairment of myocardial microcirculation. Segmental cardiac strain assessment 2DST seems useful for MIS-c cardiovascular follow-up, given its good correlation with 13 N-ammonia PET-CT derived MFR.

The Heart of Pediatric Patients with COVID-19: New Insights from a Systematic Echocardiographic Study in a Tertiary Hospital in Brazil. / O Coração de Pacientes Pediátricos com COVID-19: Novos Insights a Partir de um Estudo Ecocardiográfico Sistemático em um Hospital Terciário no Brasil.

BACKGROUND: COVID-19 pandemic represents a huge burden to the health system in the world. Although pediatric COVID-19 patients have been relatively spared compared with adults, recent reports showed an increasing number of critically ill patients with multisystemic inflammatory syndrome in children (MIS-c), with marked cardiovascular impairment. Nevertheless, little is known about the relationship between cardiac abnormalities and inflammatory and coagulation biomarkers. OBJECTIVES: to investigate echocardiographic abnormalities in pediatric patients with COVID-19 admitted to tertiary hospital. METHODS: this was a retrospective longitudinal study, based on the review of medical records and echocardiograms of patients (0-19 years) admitted to a tertiary hospital between March 30 and June 30, 2020. For statistical analysis, the significance level was set at 5% (p < 0.05). RESULTS: Forty-eight patients were enrolled, 73% with preexisting diseases, 20 (41.7%) with MIS-c. Median age was 7.5 (0-18.6) years; 27 (56.2%) were male. Median duration of hospitalization was 15.4 (2-92) days and seven (14.6%) patients died. A total of 70 echocardiograms were performed; 66.7% patients were scanned only once and 33.3% multiple times. Twenty-three (48%) patients showed echocardiographic abnormalities: eight (16.6%) left ventricle (LV) systolic dysfunction, six (12.5%) right ventricle (RV) systolic dysfunction and 12 (25%) coronary dilatation (Z-score>+2.5). Echocardiographic abnormalities were significantly associated with MIS-c, admission to the pediatric intensive care unit, multiple organ dysfunction, ventilatory/vasoactive support, and death (p<0.05). Significantly higher d-dimer (ng/mL) levels were detected in patients with LV dysfunction [16733(4157-115668) vs. 2406.5(190-95040)], RV dysfunction [25769(3422-115668) vs. 2803.5(190-95040)] and coronary artery dilation [9652.5(921-115668) vs. 2724(190- 95040)] (p<0.05). CONCLUSION: Echocardiographic abnormalities in COVID-19 pediatric patients were frequent and associated with worse clinical outcomes. Exacerbation of the inflammation and coagulation pathways may play an important role in cardiovascular injury in those patients.

FUNDAMENTO: A pandemia da COVID-19 representa uma enorme carga para o sistema de saúde do mundo. Apesar de pacientes pediátricos terem sido relativamente poupados em comparação a adultos, estudos recentes mostraram um número crescente de pacientes críticos com Síndrome Inflamatória Multisistêmica Pediátrica (SIM-P) com disfunção cardiovascular importante. No entanto, pouco se conhece a respeito da relação entre anormalidades cardíacas e biomarcadores inflamatórios e de coagulação. OBJETIVOS: Investigar anormalidades ecocardiográficas em pacientes pediátricos com COVID-19 admitidos em um hospital terciário. MÉTODOS: Este foi um estudo longitudinal retrospectivo, baseado na revisão de prontuários médicos e ecocardiogramas de pacientes (0-19 anos) admitidos em um hospital terciário entre 30 de março e 30 de junho de 2020. Para a análise estatística, o nível de significância foi estabelecido em 5% (p<0,05). RESULTADOS: Foram incluídos 48 pacientes, 73% com doenças pré-existentes, 20 (41,7%) com SIM-P. A idade mediana foi 7,5 (0-18,6) anos; 27 (56,2%) eram do sexo masculino. A duração mediana de internação foi 15,4 (2-92) dias e sete (14,6%) pacientes morreram. Um total de 70 ecocardiografias foram realizadas, 66,7% submeteram-se ao exame somente uma vez, e 33,3% várias vezes. Vinte e três (48%) pacientes apresentaram anormalidades no ecocardiograma: oito (16.6%) disfunção sistólica do ventrículo esquerdo, seis (12.5%) disfunção sistólica do ventrículo direito, e 12 (25%) dilatação da artéria coronária (Z-score>+2,5). Anormalidades ecocardiográficas foram significativamente associadas com SIM-P, admissão na unidade de terapia intensiva pediátrica, suporte ventilatório/vasoativo, e morte ( p <0,05). Níveis significativamente mais altos de d-dímero (ng/mL) foram detectados em pacientes com disfunção ventricular esquerda [16733(4157-115668) vs. 2406.5(190-95040)], disfunção ventricular direita [25769(3422-115668) vs. 2803.5(190-95040)] e dilatação da artéria coronária [9652.5(921-115668) vs. 2724(190- 95040)] (p<0,05). CONCLUSÃO: Anormalidades ecocardiográficas eram frequentes nos pacientes pediátricos com COVID-19 e associadas com piores desfechos clínicos. Exacerbação das vias de inflamação e coagulação pode exercer um importante papel na lesão cardiovascular nesses pacientes.