Duración de la onda P en las 12 derivaciones del electrocardiograma y su relación con el tiempo de conducción interauricular en pacientes con taquicardias paroxísticas supraventriculares / P wave duration in the 12 leads of the electrocardiogram and its relationship with interatrial conduction time in patients with paroxysmal supraventricular tachycardias

RESUMEN Introducción: Existen algunos estudios que relacionan parámetros de la onda P con diferentes tiempos de conducción auricular, pero no se han realizado teniendo en cuenta a cada derivación del electrocardiograma. Objetivo: Determinar la duración de la onda P (Pdur) en las 12 derivaciones y relacionarlas con el tiempo de conducción interauricular. Método: Estudio de corte transversal en 153 pacientes adultos con diagnóstico confirmado de taquicardia por reentrada intranodal (TRIN) o vías accesorias mediante estudio electrofisiológico invasivo. Resultados: Al comparar la Pdur entre sustratos arrítmicos por cada derivación, no existieron diferencias significativas, excepto en V6. En las derivaciones DII, DIII, aVR, aVF, V1 y de V3-V6 la Pdur se correlacionó con el tiempo de conducción interauricular en ambos sustratos arrítmicos. En el análisis multivariado, la Pdur constituyó un predictor independiente de tiempos de conducción interauricular ≥ 95 percentil, en las derivaciones de cara inferior y en V3, V5 y V6. Se observaron altos valores del área bajo la curva de la Característica Operativa del Receptor en las derivaciones DII (0,950; p<0,001), DIII (0,850; p<0,001) y V5 (0,891; p<0,001). Conclusiones: No existen diferencias por derivación en la Pdur al comparar casos con TRIN y vías accesorias, excepto en V6. La mayoría de las derivaciones se correlacionaron con el tiempo de conducción interauricular. La Pdur fue un predictor independiente de tiempos de conducción interauricular ≥ 95 percentil. La derivación DII presenta la mayor capacidad discriminativa para encontrar valores prolongados del tiempo de conducción interauricular.

ABSTRACT Introduction: Although some studies relate P wave parameters to different atrial conduction times, they do not consider each electrocardiogram lead separately. Objective: To determine the duration of P wave (Pdur) in the 12 leads of the electrocardiogram and relate it to the interatrial conduction time. Method: We conducted a cross-sectional study in 153 adult patients with confirmed diagnosis of atrioventricular nodal reentry tachycardia (AVNRT) or accessory pathways by invasive electrophysiological study. Results: When comparing the Pdur between arrhythmic substrates by each lead, no significant differences were found, except for V6. In leads II, III, aVR, aVF, V1 and V3-V6, Pdur was correlated with the interatrial conduction time in both arrhythmic substrates. In our multivariate analysis, the Pdur was an independent predictor of interatrial conduction times ≥ 95 percentile in inferior wall leads and in V3, V5 and V6. High values of the area under the receiver operating characteristic curve were observed in II (0.950; p<0.001), III (0.850; p<0.001) and V5 (0.891; p<0.001) leads. Conclusions: The Pdur showed no difference by leads when comparing cases with AVNRT and accessory pathways, except for V6. Most of the leads were correlated with the interatrial conduction time; Pdur was an independent predictor of interatrial conduction times ≥ 95 percentile. Lead II has the greatest discriminatory ability to find prolonged values of interatrial conduction time.

Radiofrequency catheter ablation of atrioventricular nodal reentry tachycardia in children and adolescents: a single center experience / 소아과

PURPOSE: Atrioventricular nodal reentry tachycardia (AVNRT) is less common in pediatric patients than in adult patients. Thus, data for pediatric AVNRT patients are insufficient. Hence, we aimed to analyze the patient characteristics, treatment, and any recurrences in pediatric AVNRT patients. METHODS: We reviewed the records of 50 pediatric AVNRT patients who had undergone radiofrequency catheter ablation (RFCA) between January 1998 and December 2016 at a single regional center. The patients were aged ≤18 years. RESULTS: Among 190 pediatric patients who underwent RFCA for tachyarrhythmia, 50 (26.3%; mean age, 13.4±2.6 years) were diagnosed as having AVNRT by electrophysiological study. Twenty-five patients (25 of 50, 50%) were male. Twenty patients (20 of 50, 40%) used beta-blockers before RFCA. All patients had no structural heart disease except 1 patient with valvular aortic stenosis and coarctation of the aorta. RFCA was performed using the anatomic approach under fluoroscopic guidance. The most common successfully ablated region was the midseptal region (25 of 50, 50%). Slow pathway (SP) ablation and SP modulation were performed in 43 and 6 patients, respectively. Complication occurred in 1 patient with complete atrioventricular block. During follow-up, 6 patients had recurrence of supraventricular tachycardia, as confirmed by electrocardiography. Among them, 5 underwent successful ablation at the first procedure. In 1 patient, induction failed during the first procedure. CONCLUSION: RFCA is safe and effective in pediatric AVNRT patients. However, further research is needed for establishing the endpoints of ablation in pediatric AVNRT patients and for identifying risk factors by evaluating data on AVNRT recurrence after RFCA.