RESUMEN
In this report, we present the findings in a patient who had paroxysmal supraventricular tachycardia and atrial flutter associated with the Wolff-Parkinson-White syndrome. During atrial flutter, localized atrial fibrillation was recorded in the coronary sinus (dissimilar atrial rhythms), near the accessory pathway; and during 90 minutes of observation, ventricular activation occurred solely over the normal pathway. We postulate that localized atrial fibrillation repetitively invaded the accessory pathway and rendered it refractory to conduction by flutter impulses.
Asunto(s)
Aleteo Atrial/fisiopatología , Atrios Cardíacos/fisiopatología , Taquicardia Paroxística/fisiopatología , Síndrome de Wolff-Parkinson-White/fisiopatología , Fibrilación Atrial/fisiopatología , Nodo Atrioventricular/fisiopatología , Fascículo Atrioventricular/fisiopatología , Estimulación Cardíaca Artificial , Electrocardiografía , Femenino , Humanos , Persona de Mediana EdadRESUMEN
Two patients who presented by scalar ECG with an A-V junctional tachycardia were demonstrated during an electrophysiologic evaluation to have an atrial tachycardia without P waves in the surface ECG. Case 1 had an atrial tachycardia that conducted through the A-V node with a Wenckebach block. Atrial activity was recorded only from the proximal portion of the coronary sinus and from right atrial areas near the tricuspid valve. Case 2 had an atrial tachycardia that abruptly began and terminated following carotid sinus massage. Atrial activity was recorded only in the coronary sinusos, and pacing at that site resulted in atrial capture, with Wenckebach conduction to the ventricles. These observations demonstrate that an atrial tachycardia without P waves can simulate A-V junctional tachycardia with or without Weckebach block. Such findings may have a bearing on some important electrophysiologic concepts such as the origin of A-V junctional rhythms and the need for atrial participation in A-V nodal re-entry.