Late-onset periodic bradycardia during vagus nerve stimulation in a pediatric patient. A new case and review of the literature.

BACKGROUND: Epilepsy is a common disease in the world. Around 10-40% of patients who suffer epilepsy will have intractable seizures. When resective epilepsy surgery is not possible, vagus nerve stimulation (VNS) can be an option. The most common side effects associated with VSN therapy are hoarseness, throat pain and coughing. Cardiac arrhythmia has been reported during lead tests performed during implantation of the device, but few cases during regular treatment. We report a new child where vagally induced bradyarrhythmia, perfectly correlated with the stimulation periods. CLINICAL REPORT: 13-year-old girl with refractory myoclonic-astatic epilepsy since the age of two. When she was five years old, a VNS was implanted with complete resolution of her seizures. But when she was 13, she began with sudden falls with loss of consciousness lasting less than 10 s, which were similar to her previous epileptic drop-attacks. Continuous ECG recording was normal but electrocardiography showed a bradycardia of 45 bpm with a syncope-like episode. It was necessary to turn off the VNS. CONCLUSIONS: To our knowledge, there are just three pediatrics and four adults patients described in the literature with this severe and life-threatening side effect. Cardiac complications of VNS therapy are very infrequent but should alert clinicians to its possibility. A cardiac evaluation is mandatory before VNS implantation and periodically thereafter (probably between one or three years).

Alteraciones electrocardiográficas y ecocardiográficas en mujeres adolescentes con anorexia nerviosa / Electrocardiographic and echocardiographic abnormalities in female adolescents with anorexia nervosa

INTRODUCCIÓN: el objetivo del estudio es describir los hallazgos electrocardiográficos y ecocardiográficos en mujeres adolescentes con anorexia nerviosa y correlacionarlos con parámetros clínicos. PACIENTES Y MÉTODOS: estudio observacional, retrospectivo, de casos y controles. Se estudiaron 98 mujeres adolescentes ingresadas en un hospital terciario por anorexia nerviosa restrictiva (ANR) durante los últimos 15 años, en las que se realizó valoración electrocardiográfica y ecocardiográfica al ingreso. RESULTADOS: la edad media fue similar en ambos grupos (14,6 ± 2,0 frente a 14,7 ± 2,0 años). Las pacientes con ANR presentaban menor frecuencia cardiaca (57 ± 12 frente a 72 ± 13 lpm), voltajes más bajos (rV5 = 1,1 ± 0,5 frente a 1,6 ± 0,4 mV) y menor masa ventricular izquierda (65,7 ± 14,8 frente a 90 ± 15,3 g/m2) que las pacientes controles. No se encontraron diferencias en la medición del QTc. En las pacientes con ANR, la bradicardia no se correlacionó con el peso (r = -0,20; p = 0,05), ni con el índice de masa corporal (IMC) (r = 0,02; p = 0,22) al ingreso. El grosor del septo interventricular y la masa del ventrículo izquierdo fueron significativamente menores en los pacientes con ANR (5,7 mm frente a 6,8 mm, p <0,001; 65,7 frente a 90 g/m2; p <0,001). La masa ventricular izquierda se correlacionó de forma significativa con el IMC (r = 0,21; p <0,001) y con la frecuencia cardiaca (FC) (r = -0,225; p <0,001). CONCLUSIONES: las alteraciones cardiacas fueron más prevalentes en pacientes con ANR. La bradicardia, los trastornos de la repolarización ventricular y la disminución de la masa cardiaca fueron los más frecuentemente identificados

INTRODUCTION: the aim of the study was to describe the electrocardiographic and echocardiographic findings in female adolescents with anorexia nervosa and to assess their correlation with clinical variables. PATIENTS AND METHODS: we conducted a retrospective observational case-control study. The analysis included 98 female adolescents admitted to a tertiary hospital due to anorexia nervosa over the last 15 years, all of who underwent an electrocardiographic and echocardiographic evaluation. RESULTS: the mean age was similar in both groups: 14.6 ± 2.0 years in cases vs. 14.7 ± 2.0 years in controls. Patients with anorexia had significantly lower heart rates (57 ± 12 vs. 72 ± 13 bpm), a smaller R-wave in V5 (1.1 ± 0.5 vs 1.6 ± 0.4 mV) and a lesser left ventricular mass (65.7 ± 14.8 vs 90 ± 15.3 g/m2) compared to controls. We found no differences in the QTc interval. In patients with anorexia, the presence of bradycardia was not correlated to weight (r = -0.20, p = 0.05) or body mass index (r = 0.02, p = 0.22) at admission. We found that the left ventricular mass was significantly correlated to the body mass index (r = 0.21, p <0.001,) and the heart rate (r = -0.225, p <0.001). CONCLUSIONS: cardiac abnormalities were more prevalent in patients with anorexia nervosa. Bradycardia, changes in ventricular repolarization, and a lesser left ventricular mass were the most frequent abnormalities in our sample

[Effects of cisapride on QT interval in children]. / Efecto de la cisaprida sobre el intervalo QT en niños.

This prospective study evaluated the effects of cisapride on corrected QT interval (QTc) in infants and children. From October 2000 to March 2003 two electrocardiograms (ECG) were obtained for 175 children (ranging in age from 1.5 months to 16.8 years), before and after 15 days of treatment with cisapride (0.2 mg/kg/dose, 3-4 times/day). A single posttreatment ECG was also obtained for 24 patients (ranging in age from 1.5 month to 15.8 years). No statistically significant differences were found between the mean QTc interval before (0.390 [0.018 s]) and after treatment (0.391 [0.018 s]). In patients for whom only a posttreatment ECG recording was performed, mean QTc interval was 0.399 (0.018 s). The QTc interval was never longer than 0.450 s in any of the children. In our experience the use of cisapride at therapeutic doses in infants and children who have no associated risk factors does not significantly prolong QTc interval.

Efectos de la cisaprida sobre el intervalo QT en niños / Effects of cisapride on QT interval in children

Se valoró de forma prospectiva el efecto en el intervalo QT corregido (QTc) del tratamiento con cisaprida en niños. Desde octubre de 2000 a marzo de 2003, se realizó un electrocardiograma (ECG) basal y otro a los 15 días de tratamiento con cisaprida (o,2 mg/kg/dosis, 3-4 veces/día) a 175 niños (edad entre 1, 5 meses y 15, 8 años). No se encontraron diferencias estadísticamente significativas entre el intervalo QTc medio basal (0, 390 +- 0, 018 s) y postratamiento (0, 391+-0,018 s). En los enfermos con un único ECG postratamineto, el intervalo QTc medio fue de 0, 399+-0,018 s. En ningún caso el intervalo QTc superó los 0,450 s. Según nuestra experiencia, la utilización de cisaprida en dosis terapéticas en niños sin factores de riesgo asociados no prolonga significativamente el intervalo QTc (AU)

Muerte súbita y fibrilación ventricular de posible origen isquémico en un niño con miocardiopatía hipertrófica / Sudden Death and Ventricular Fibrillation of Possible Ischemic Origin in a Boy with Hypertrophic Cardiomyopathy

Se presenta el caso de un paciente de 11 años que ingresa por un cuadro de fibrilación ventricular y que es diagnosticado de miocardiopatía hipertrófica medioseptal. La analítica de ingreso y la evolución anatómica miocárdica sugieren etiología isquémica. Se revisan los factores de riesgo para muerte súbita, su relación con la isquemia miocárdica y la etiología de la misma en la miocardiopatía hipertrófica (AU)