Fibrilación auricular por vía accesoria con patrón de preexcitación ventricular: Informe de un caso / Atrial fibrillation by accessory pathway with pattern of ventricular pre-excitation: A case report

RESUMEN La fibrilación auricular por vía accesoria es una peligrosa enfermedad que puede provocar muerte súbita; es poco frecuente y necesita una conducta exacta, mucho más si aparece un patrón de preexcitación ventricular. Se presenta el caso de un adolescente masculino de 17 años de edad y piel blanca, con antecedentes de palpitaciones cortas a esfuerzos moderados y pérdida ocasional del conocimiento de breve duración, sin otra sintomatología asociada. Al momento del ingreso presenta un cuadro de palpitaciones, fatiga, palidez e hipotensión arterial, y en el electrocardiograma se observa una taquicardia con QRS ancho, irregular, con onda delta y frecuencia ventricular rápida, que fue interpretada como fibrilación auricular preexcitada. Se realizó cardioversión eléctrica sincronizada al QRS con 100 julios y se logró restaurar el ritmo sinusal con patrón electrocardiográfico de preexitación ventricular (síndrome de Wolff-Parkinson-White).

ABSTRACT Atrial fibrillation by accessory pathway is a dangerous disease that can cause sudden death, it is rare and it needs a careful management, even more, if a pattern of ventricular pre-excitation appears. The case of a white skin 17-year-old teenager with a history of short palpitations at moderate effort, and occasional loss of consciousness of short duration, without other associated symptoms, is presented. At the moment of admission, he presents palpitations, fatigue, pallor and low blood pressure; in the electrocardiogram a tachycardia with wide, irregular QRS, with delta wave and rapid ventricular rate is observed, which was interpreted as pre-excited atrial fibrillation. Synchronized electrical cardioversion to QRS with 100 joules was performed, and sinus rhythm was restored with electrocardiographic pattern of ventricular pre-excitation (Wolff-Parkinson-White syndrome).

Accessory pathway induced dilated cardiomyopathy / 中华实用儿科临床杂志

Accessory pathway-induced dilated cardiomyopathy is a new diagnosis proposed recently.Pre-excitation of part of the myocardium may mediate electrical and mechanical dyssynchrony,which will result in decreased left ventricular systolic function and increased diameter of left ventricle in patients with right-sided overt accessory pathways (type B ventricular preexcitation).Its features are listed as follows:(1) Incessant and prolonged tachyarrhythmia never happened.Tachycardiomyopathy and other causes of dilated cardiomyopathy are excluded.(2) Right-sided overt accessory pathways are shown by electrocardiogram.(3)Echocardiography indicates dyssynchronous left ventricle contraction,decreased left ventricular systolic function and increased diameter of left ventricle.Normal interventricular septal motion,recovered left ventricular and reversed left ventricular remodeling can be realized by radiofrequency ablation with a good prognosis.To infant patients,taking anti arrhythmia drugs to inhibit the conduction of the accessory pathway was recommended.

Clinical characteristics of ventricular preexcitation dilated cardiomyopathy induced by accessory pathway / 中华实用儿科临床杂志

Objective To discuss the characteristics,diagnosis,mechanism and the prognosis of dilated cardiomyopathy (DCM) induced by accessory pathway (AP).Methods The clinical,electrophysiological and echocardiographic characteristics in four cases,who were diagnosed as AP-induced DCM in the Department of Pediatric Cardiology of Beijing Anzhen Hospital,Capital Medical University from Mar.2011 to Aug.2012,were analyzed before and after ablation.Results The electrocardiograms of the 4 patients all indicated type B ventricular preexcitation.The locations of the APs were the right-sided anteroseptum and the free wall.Dyschronous contractions between posterior wall of left ventricle and interventricular septum were demonstrated by M-Mode echo.The basal segments of the interventricular septum turned thin and moved similar to an aneurysm,with typical bulging during end-systole,which was observed in all cases by two-dimension echo.Dyschronous left ventricular contraction was shown by speckle tracing technique.All patients received successful radio frequency current ablations.Their physical activities and growth improved greatly in the 4 cases.The echocardiographic data demonstrated that their left ventricular contraction recovered to synchrony shortly after the ablation,left ventricular ejection fraction recovered to normal and left ventricular end diastolic diameter decreased to almost normal gradually during the follow-up.Conclusions Overt right-sided APs localized in anteroseptum or free wall may have adverse effects on ventricular wall motion and left ventricular function.They can even result in DCM.Dyssynchronous ventricular contraction induced by right-sided overt accessory pathway may be the vital mechanism.AP-induced DCM is an indication for ablation with good prognosis.