Intermittent atrial undersensing in single-lead VDD pacemakers in patients with bradycardia-sensitive repolarization: a possible mechanism for ventricular arrhythmia.
Intermittent atrial undersensing in patients with single-lead VDD pacemakers is regarded as being of limited clinical significance. Nevertheless, in patients with bradycardia-mediated repolarization abnormalities, undersensing could result in RR-interval oscillations due to changes in pacemaker mode and this could act as a trigger for the initiation of torsades de pointes. We report our findings in three patients, which demonstrate the functioning of this trigger mechanism for ventricular arrhythmias.
Palanca
Víctor
V
Unidad de Arritmias, Instituto Cardiovascular del Consorcio Hospital General Universitario de Valencia, Valencia, Spain. palanca_vic@gva.es
Navarro
Alejandro
A
Jiménez
Javier
J
Quesada
Aurelio
A
Morell
Salvador
S
Roda
José
J
D000368:Aged; D000369:Aged, 80 and over; D001145:Arrhythmias, Cardiac / Q000209:etiology* / Q000628:therapy*; D054537:Atrioventricular Block / Q000503:physiopathology* / Q000628:therapy*; D001919:Bradycardia / Q000503:physiopathology* / Q000628:therapy*; D004562:Electrocardiography; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006352:Heart Ventricles; D006801:Humans; D010138:Pacemaker, Artificial