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Intermittent capture of the right ventricular outflow tract by atrial pacing in a patient with a dual-chamber
Julio Daniel Pastori1, Hugo Ariel Garro, Adrián Baranchuk
1División Cardiología, Centro de Arritmias Cardíacas de la Ciudad Autónoma de Buenos Aires, Hospital General de Agudos JM Ramos Mejía, Buenos Aires, Argentina. juliodpastori@gmail.com
Abstract:
We describe a previously unreported phenomenon of intermittent outflow right ventricular tract capture from the atrial lead of a dual-chamber pacemaker. This was more obvious at slower paced atrial rates and disappeared by decreasing the atrial pulses voltage. Electroanatomical mapping showed that the onset of activation was nearly simultaneous at the insertion site of the atrial lead and at an intermediate level of the right ventricular outflow tract. This exceptional finding might be erroneously diagnosed as due to pseudo-pseudo fusion beats.
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