MedPath

Evaluation of Ventricular Pacing Suppression Algorithms in Dual Chamber Pacemaker

Not Applicable
Completed
Conditions
Pacemaker
Heart Failure
Sick Sinus Syndrome
Interventions
Device: Pacemaker with Fixed long AV delay
Device: Pacemaker with IRSplus algorithm on
Device: Pacemaker with VpS® algorithm on
Registration Number
NCT03843242
Lead Sponsor
Keimyung University Dongsan Medical Center
Brief Summary

The recent study using IRSplus and VpS algorithm from Biotronik pacemaker showed the significant reduction in ventricular pacing to less than 3%.

The purpose of this study is to evaluate the efficacy of IRSplus and VpS algorithm in reducing ventricular pacing compared with conventional DDD pacing with a fixed AV delay.

Detailed Description

The adverse cardiac outcomes due to right ventricular apical pacing with dual chamber pacemakers have been widely observed such as ventricular dyssynchrony resulting in reduced left ventricular function, increased risk of heart failure and atrial fibrillation. To minimize the ventricular pacing, manufacturers of pacemaker have made an effort to develop special algorithms designed to deliver right ventricular pacing only in case of demonstrated persistent long PR interval or repetitively lacking intrinsic ventricular activation.

Currently, there are three methods and algorithms are available with a pacemaker from the Biotronik SE \& Co. KG to minimize right ventricular pacing as follows; DDD mode with fixed longer atrioventricular (AV) delay than intrinsic conduction time; Intrinsic rhythm support (IRSplus); Ventricular pacing suppression (VpS).

In the real world, it is the most common practice to program the DDD(R) mode with fixed long AV delay because of physician's concerns about the possible failure of an algorithm or long pause being resulted from 2 consecutive loss of AV conduction by the algorithm. However, the main disadvantage of a fixed with long AV delay is that the prolonged total atrial refractory period (TARP) results in changes of the upper rate behavior (i.e., pseudo-Wenckebach AV block and subsequently 2:1 block at lower atrial tracking rates). The possibility of pacemaker-mediated tachycardia is getting high if the post-ventricular atrial refractory period (PVARP) is shortened to compensate. Furthermore, there is a high chance to have fusion/pseudo-fusion of ventricular pacing in a fixed long AV delay because the AV conduction is dynamic according to the heart rate.

The recent systematic review showed that there are no significant differences between the pacing modes for mortality, heart failure, stroke, and atrial fibrillation (AF) in patients with sinus node dysfunction (SND) without AV block. However, the dual chamber pacemaker is still recommended in patients with SND due to lack of tools to identify patients at high risk of developing the complete AV block. The meta-analysis about the effect of the reduction in unnecessary ventricular pacing using a sophisticated algorithm in patients with SND showed there are no benefits in clinical outcomes compared with conventional DDD mode. But the percentage of ventricular pacing in ventricular pacing reduction modality group was not negligible between 1\~11.5%. The result might be changed if we have data with a more significant reduction in ventricular pacing using difference algorithm. The recent study using IRSplus and VpS algorithm from Biotronik pacemaker showed the significant reduction in ventricular pacing to less than 3%.

The purpose of this study is to evaluate the efficacy of IRSplus and VpS algorithm compared with conventional DDD pacing with a fixed AV delay.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
146
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

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
Pacemaker with IRSplus algorithm onPacemaker with Fixed long AV delayIRS 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.
Pacemaker with IRSplus algorithm onPacemaker with IRSplus algorithm onIRS 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.
Pacemaker with Fixed long AV delayPacemaker with Fixed long AV delay1. Patients who meet the inclusion criteria and is implanted with a Biotronik Enitra 8 DR-T pacemaker are eligible. 2. The pacemaker was programmed with a long and fixed atrioventricular interval for the first 3 months. 3. 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
Pacemaker with VpS® algorithm onPacemaker with Fixed long AV delayVp 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.
Pacemaker with VpS® algorithm onPacemaker with VpS® algorithm onVp 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.
Primary Outcome Measures
NameTimeMethod
Percentage of right ventricular pacingDuring 10 ~ 15 months after the study enrollment

the right ventricle pacing percentage appeared on the pacemaker interrogation

Secondary Outcome Measures
NameTimeMethod
Percentage of atrial high rate episodeDuring 12 months after randomization (15 months after enrollment)

Percentage of atrial high rate episode appeared on the pacemaker interrogation

New onset atrial fibrillationDuring 12 months after randomization (15 months after enrollment)

Percentage of patients with new onset atrial fibrillation during the observation period

Occurrence of heart failureDuring 12 months after randomization (15 months after enrollment)

Percentage of patients who experienced symptomatic heart failure during the observation period

Trial Locations

Locations (6)

Division of Cardiology, Department of Internal Medicine, Yeungnam University Hospital

🇰🇷

Daegu, Korea, Republic of

Dongguk University Medical Center

🇰🇷

Ilsan, Korea, Republic of

Pusan National University Hospital

🇰🇷

Pusan, Korea, Republic of

Daegu Fatima Hospital

🇰🇷

Daegu, Korea, Republic of

Division of Cardiology, Department of Internal Medicine, Kyungpook National University Hospital

🇰🇷

Daegu, Korea, Republic of

Division of Cardiology, Department of Internal Medicine, Daegu Catholic University Medical Center

🇰🇷

Daegu, Korea, Republic of

© Copyright 2025. All Rights Reserved by MedPath