Abstract Introduction Implantable cardioverter-defibrillators (ICDs) for
cardiac resynchronization therapy (CRT-D) with the capability of LV
sensing enable the assessment of interventricular delays in ventricular
(VT) and supraventricular tachycardias (SVT). Methods and Results In
total, 1078 EGM recordings of VT or VF episodes were investigated that
have been transmitted via Home MonitoringⓇ. Only those EGM recordings
showing the onset of the tachyarrhythmia were used for investigation. In
the 623 cases eligible for evaluation left-sided VTs could be identified
in 349 cases, right-sided VTs in 252 cases. SVTs with a 1:1 antegrade
conduction were found in 22 cases. VT can present three different
interventricular delays whereby the right-ventricular sensed event (RVs)
is either preceding the left-ventricular sensed event (LVs), or the LVs
is preceding RVs, or there can be a simultaneous occurrence of RVs and
LVs. In SVTs, either the LVs events were delayed or occurred
simultaneously with the RVs events. SVT cases with LVs preceding the RVs
events were not found. Conclusion The LV-EGM channel enables to
distinguish between left- and right-sided premature ventricular
complexes. The assessment of the interventricular delay in VTs is useful
to differentiate between a possible apical-, left- or right-sided origin
of the VT but not to identify SVTs. Key Words Implantable Cardioverter
Defibrillator (ICD), Cardiac resynchronization therapy (CRT), LV
sensing, RV sensing, Ventricular tachycardia, Supraventricular
tachycardia, Left bundle branch block, Heart failure, Interventricular
conduction delay
Cardiac Resynchronization Therapy for Left Ventricular Dysfunction Induced by Chronic Right Ventricular Pacing in a Child
