Socioeconomic Factors Influencing Pediatric Peak Oxygen Consumption Prediction.

OBJECTIVE: To determine if socioeconomic status (SES) has a greater effect than standard demographic values on predicted peak oxygen consumption (pVO2). STUDY DESIGN: We conducted a single-institution, retrospective analysis of maximal cardiopulmonary exercise test (CPET) data from 2010 to 2020 for healthy patients age <19 years with body mass index (BMI) percentile (BMI%) between 5-95. Data were sorted by self-identified race, BMI%, and adjusted gross income (AGI); AGI served as a surrogate for SES. Mean percent predicted pVO2 (pppVO2) was compared between groups. Linear regression was used to adjust for differences. RESULTS: A total of 541 CPETs met inclusion criteria. Mean pppVO2 was 97% ± 22.6 predicted (P < .01) with 30% below criterion standard for normal (85% predicted). After excluding unknown AGI and race, 418 CPETs remained. Mean pppVO2 was lower for Blacks (n = 36) and Latinx (n = 26) compared with Whites (n = 333, P < .01). Mean pppVO2 declined as AGI decreased (P < .01). The differences in pppVO2 between racial categories remained significant when adjusted for BMI% (Black r = -7.3, P = .035; Latinx r = -15.4, P < .01). These differences both decreased in magnitude and were no longer significant when adjusted for AGI (Black r = -6.0, P = .150; Latinx r = -9.3, P = .06). CONCLUSIONS: Lower SES correlates with lower measured cardiovascular fitness and may confound data interpretation. When using normative reference ranges in clinical decision making, providers should recognize that social determinants of health may influence predicted fitness. Social inequities should be considered when assessing pediatric cardiovascular fitness.

Electrocardiogram as a Lyme Disease Screening Test.

OBJECTIVE: To examine the association between electrocardiographic (ECG) evidence of carditis at the time of Lyme disease evaluation and a diagnosis of Lyme disease. STUDY DESIGN: We performed an 8-center prospective cohort study of children undergoing emergency department evaluation for Lyme disease limited to those who had an ECG obtained by their treating clinicians. The study cardiologist reviewed all ECGs flagged as abnormal by the study sites to assess for ECG evidence of carditis. We defined Lyme disease as the presence of an erythema migrans lesion or a positive 2-tier Lyme disease serology. We used logistic regression to measure the association between Lyme disease and atrioventricular (AV) block or any ECG evidence of carditis. RESULTS: Of the 546 children who had an ECG obtained, 214 (39%) had Lyme disease. Overall, 42 children had ECG evidence of carditis, of whom 24 had AV block (20 first-degree). Of the patients with ECG evidence of carditis, only 21 (50%) had any cardiac symptoms. The presence of AV block (OR 4.7, 95% CI 1.8-12.1) and any ECG evidence of carditis (OR 2.3, 95% CI 1.2-4.3) were both associated with diagnosis of Lyme disease. CONCLUSIONS: ECG evidence of carditis, especially AV block, was associated with a diagnosis of Lyme disease. ECG evidence of carditis can be used as a diagnostic biomarker for Lyme disease to guide initial management while awaiting Lyme disease test results.

Mejoría de la función ventricular sistólica en pacientes pediátricos y/o portadores de cardiopatías congénitas sometidos a resincronización cardíaca / Cardiac resynchronization therapy is associated with improved systolic ventricular function in pediatrics and congenital heart disease

Antecedentes: Diversas publicaciones han validado el uso terapéutico de resincronización cardíaca en adultos portadores de insuficiencia cardíaca, pero la experiencia en pacientes pediátricos y en pacientes portadores de cardiopatías congénitas es limitada. Objetivo: Determinar los resultados de resincronización cardíaca en pacientes pediátricos y/o portadores de cardiopatías congénitas.Método: Revisión retrospectiva de los antecedentes clínicos, ecocardiogramas y electrocardiogramas en 40 pacientes consecutivos con disfunción ventricular, tratados con resincronización cardíaca entre septiembre 2002 y julio 2006 en el Children's Hospital Boston.Resultados: Al momento del implante la mediana de edad fue 16,4 años (4 meses-47años). Cinco pacientes teníancorazón estructuralmente normal, 33 eran portadores de cardiopatía congénita y 2 tenían diagnóstico de miocardiopatía. Dieciocho pacientes (45 por ciento) tenían marcapaso definitivo. La mediana de seguimiento fue 1,7 años (2 meses-4 años). Cinco pacientes no usan su sistema de estimulación biventricular. La función ventricular mejoró en 30/35 pacientes (85,7 por ciento). La fracción de eyección aumentó de 31,4 a 41,5 por ciento, principalmente como consecuencia de disminución del volumen ventricular izquierdo de fin de sístole, con mínima disminución del volumen ventricular izquierdo de fin de diástole. Cinco pacientes no respondieron y no se identificaron factores predictores de los no respondedores. Análisis por intención de tratar reflejamejoría en 30/40 pacientes (75 por ciento). Conclusión: La resincronización cardíaca produce mejoría de la función ventricular en un porcentaje significativo de unapoblación seleccionada de pacientes pediátricos y/o portadores de cardiopatías congénitas, predominantemente asociada con disminución del volumen ventricular izquierdo de fin de sístole. Estos hallazgos pueden tener importante relevancia en el tratamiento a largo plazo de este grupo de pacientes.

Transient prolonged corrected QT interval in Lyme disease.

Lyme disease, caused by the spirochete Borrelia burgdorferi, has known cardiovascular effects typically manifesting in varying degrees of atrioventricular block. Three patients presented with QT interval prolongation associated with Lyme disease, a previously unreported manifestation of Lyme carditis. Implications and a proposed clinical management approach are discussed.