Evaluation of Ventricular Pacing Suppression Algorithms in Dual Chamber Pacemaker (LEADER)
Sick Sinus Syndrome, Pacemaker, Heart Failure
About this trial
This is an interventional diagnostic trial for Sick Sinus Syndrome
Eligibility Criteria
Inclusion Criteria:
- Sick sinus syndrome
- No evidence of 2nd and 3rd degree AV block
- Provide written informed consent
- Age ≥ 20 years old
Exclusion Criteria:
- 2nd and 3rd degree AV block
- History of AF
- patients with older version of pacemaker
- Life expectancy ≤ one year
- Pregnant or lactating women
Sites / Locations
- Daegu Fatima Hospital
- Division of Cardiology, Department of Internal Medicine, Kyungpook National University Hospital
- Division of Cardiology, Department of Internal Medicine, Yeungnam University Hospital
- Division of Cardiology, Department of Internal Medicine, Daegu Catholic University Medical Center
- Dongguk University Medical Center
- Pusan National University Hospital
Arms of the Study
Arm 1
Arm 2
Arm 3
Experimental
Experimental
Experimental
Pacemaker with Fixed long AV delay
Pacemaker with VpS® algorithm on
Pacemaker with IRSplus algorithm on
Patients who meet the inclusion criteria and is implanted with a Biotronik Enitra 8 DR-T pacemaker are eligible. The pacemaker was programmed with a long and fixed atrioventricular interval for the first 3 months. Definition of fixed AV delay (than intrinsic AV conduction) • If P-wave exists: intrinsic AV conduction time = As ~ Vs interval in the marker channel sensed AV delay = intrinsic AV conduction time + 20 msec paced AV delay = sensed AV delay + 30 msec • If no P-wave exits: intrinsic AV conduction time = Ap ~ Vs interval in the marker channel paced AV delay = intrinsic AV conduction time + 20 msec sensed AV delay = paced AV delay - 30 msec • If the intrinsic AV conduction time is ≥ 300ms, make paced/sensed AV delay 350/320 msec
Vp Suppression ON algorithm: This feature promotes the intrinsic AV conduction by only pacing the ventricle when intrinsic conduction becomes unstable or disappears. Depending on the presence or absence of AV conduction, the feature is implemented either in the ventricular pacing suppression state ADI(R), which promotes the intrinsic conduction, or in the DDD(R) ventricular pacing state Vp DDD(R), which provides ventricular pacing. Automatic switching capabilities between those two states promotethe intrinsic conduction as much as possible without harming the patient. Scheduled Vs searching tests look for intrinsic conduction using an extended AV delay of 450ms.
IRS plus algorithm: This algorithm incorporates two different functions: the first is scan hysteresis, which better enables the heart to pace on its own by periodically extending the search time for its natural pacing stimulus (the intrinsic AV conduction) over six consecutive atrial cycles. The second is the repetitive hysteresis, which recognizes when the heart is not pacing on its own (a consistent loss of intrinsic AV conduction lasting for six consecutive atrial cycles) and switches the mode of the device from extended to basic atrioventricular (AV) delay.