Comparison of AAIsafeR and DDD Modes in Non-selected Patients (CAN-SAVE R)

A Prospective Canadian Multi-Center Randomized Study; Spontaneous AtrioVEntricular Conduction PReservation

1 Purpose

In patients with sinus node dysfunction (SND), the use of AAI mode is rare. In paroxysmal high-degree or complete atrio-ventricular (AV) block, paroxysmal vagally-mediated bradycardia, single chamber atrial pacemakers are contraindicated although ventricular support is only rarely needed. As a result, these patients are usually exposed to an unnecessary high proportion of ventricular pacing due to the programming of the system to DDD mode for preventive safety reasons. This drains the pulse generator battery, and more importantly has long-term adverse effects on ventricular function in a subset of vulnerable patients, leading to left ventricular (LV) asynchrony, mitral regurgitation and increased left atrium (LA) size. The deleterious effects of right ventricular (RV) pacing, which increased heart failure (HF) morbidity/mortality, atrial fibrillation (AF) and related adverse events have been highlighted in several large clinical studies. Limiting RV pacing in non-dependant patients is therefore desirable.

The Symphony DR 2550 cardiac pacemakers (SORIN Group, Montrouge, France) offer a new pacing mode that automatically switches from AAI(R) mode to DDD(R) or DDI(R) in event of severe atrioventricular conduction disorder, returning spontaneously to AAI(R) mode as soon as the spontaneous AV conduction has resumed. This particular mode is called the AAIsafeR2(R).

The objective of this study is three-fold: to demonstrate that AAIsafeR2 mode (i) reduces the percentage of ventricular pacing in patients with a spontaneous AV conduction and (ii) prevents atrial arrhythmias by improving atrial hemodynamics and (iii) improves the long-term hemodynamic status of implanted patients in comparison to the "standard" DDD mode, set with long AV Delays (DDD Long AVD).

The scientific soundness lying in this study is a proposal of an optimal programming of dual-chamber pacemakers (PM) with regard to the preservation of spontaneous AV conduction.

Study Overview

• Status: Completed
• Conditions: Any Patient Who Fulfills the Inclusion Criteria to be Implanted With a Dual Chamber Pacemaker Maybe Included in the Study as Per ACC/AHA Guidelines
• Intervention / Treatment: Procedure: Symphony Dual Chamber Rate Responsive Device

Detailed Description

In patients with sinus node dysfunction (SND), the use of AAI mode is rare. In paroxysmal high-degree or complete atrio-ventricular (AV) block, paroxysmal vagally-mediated bradycardia, single chamber atrial pacemakers are contraindicated although ventricular support is only rarely needed. As a result, these patients are usually exposed to an unnecessary high proportion of ventricular pacing due to the programming of the system to DDD mode for preventive safety reasons. This drains the pulse generator battery, and more importantly has long-term adverse effects on ventricular function in a subset of vulnerable patients, leading to left ventricular (LV) asynchrony, mitral regurgitation and increased left atrium (LA) size. The deleterious effects of right ventricular (RV) pacing, which increased heart failure (HF) morbidity/mortality, atrial fibrillation (AF) and related adverse events have been highlighted in several large clinical studies. Limiting RV pacing in non-dependant patients is therefore desirable.

The Symphony DR 2550 cardiac pacemakers (SORIN Group, Montrouge, France) offer a new pacing mode that automatically switches from AAI(R) mode to DDD(R) or DDI(R) in event of severe atrioventricular conduction disorder, returning spontaneously to AAI(R) mode as soon as the spontaneous AV conduction has resumed. This particular mode is called the AAIsafeR2(R).

The objective of this study is three-fold: to demonstrate that AAIsafeR2 mode (i) reduces the percentage of ventricular pacing in patients with a spontaneous AV conduction and (ii) prevents atrial arrhythmias by improving atrial hemodynamics and (iii) improves the long-term hemodynamic status of implanted patients in comparison to the "standard" DDD mode, set with long AV Delays (DDD Long AVD).

The scientific soundness lying in this study is a proposal of an optimal programming of dual-chamber pacemakers (PM) with regard to the preservation of spontaneous AV conduction.

2 Study devices

Classification Name Manufacturer Name Cardiovascular permanent pacemaker pulse generator SORIN Group Symphony ™ DR2550

3 Summary of study objectives

The aims of this study are to assess the clinical benefits resulting from AAIsafeR2 by comparison with standard dual chamber programming (DDD) with a long AV Delay.

The benefits will be assessed by comparing the percentage of ventricular pacing, the incidence of atrial arrhythmias, and the evolution of the hemodynamic status as observed through echo parameter and ANP/BNP measurements.

The primary objectives of the study are:

to demonstrate the effectiveness of AAIsafeR2 to preserve natural AV conduction as compared to DDD Long AVD. For this purpose, ventricular pacing ratio as retrieved from PM memory will be assessed on a mid-term period (1 year) by inter-groups comparison of:

• Mean V pacing (%)
• Proportion of patients with a V pacing ratio < 1 %.

to demonstrate the effectiveness of AAIsafeR2 to reduce AF incidence on a long-term basis (3-year follow-up) by analyzing in the randomized branches:

• the cumulative time in AF (as documented by PM memory)
• the total number of AF episodes (as documented by PM memory)
• the number of patients who present a cumulative time in AF>30% of the follow-up period (as documented by PM memory)
• the proportion of patients who turned into persistent AF during the study.
• the proportion of patients who turned into permanent AF during the study.

to compare the effects of AAISafeR2 vs. DDD Long AVD on LV function, mitral regurgitation and LA dimensions on a long-term basis (3-year follow-up) by comparing:

• LV ejection fraction (EF) and volumes
• Left atrium dimensions
• Mitral regurgitation severity as measured by standard echocardiographic methods.

The secondary objectives of this study are to report and compare the following in each randomized arm of the study:

Total mortality CHF-related mortality and hospitalizations Evolution of systemic blood pressures, as estimated by ANP/BNP measurements AF-related adverse events, such as strokes/TIA's and cardioversions The evolution of cardiac asynchrony [inter-ventricular (RV-LV) and intra-ventricular (4 segments), as assessed by TDI technics] The evolution of conduction disturbances in patients presenting unknown or under estimated atrio-ventricular blocks on a long-term basis (intra-group analysis). Stratification by pacing indications and cardiopathies.

• Study Type: Interventional
• Enrollment (Actual): 450
• Phase: Phase 3

Contacts and Locations

Study Locations

• Canada
  • Alberta
    • Edmonton, Alberta, Canada, T6L 5X8
      • Grey Nuns Hospital
    • Edmonton, Alberta, Canada
      • Royal-Alex hospital
  • Ontario
    • Kingston, Ontario, Canada, K7L 2V7
      • Kingston General Hospital
    • Newmarket, Ontario, Canada
      • Southlake Hospital
    • Toronto, Ontario, Canada
      • St Mike's hospital
  • Quebec
    • Montreal, Quebec, Canada, H1t 1c8
      • Institute de Cardilogie, Montreal Heart Institute
    • St Jerome, Quebec, Canada, J7Z 5T3
      • Hotel-Dieu St Jerome
    • Ste Foy, Quebec, Canada
      • Laval Hospital
    • Trois-Rivieres, Quebec, Canada
      • Trois-Riviere general hospital
  • Saskatchewan
    • Saskatoon, Saskatchewan, Canada
      • Saskatoon Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Inclusion criteria / Indications Any patient who fulfils one or more of the official guidelines to be implanted with a dual-chamber pacemaker (primo-implantation) may be included in the study.

Exclusion Criteria:

Exclusion criteria / Contraindications

The patients presenting with one or more of the following characteristics cannot be included:

• Permanent complete AV block
• Permanent atrial and/or ventricular arrhythmias
• already implanted with a cardioverter-defibrillator (ICD)
• Likely to have a cardiac surgery in the next six months, mainly for:
• severe coronary artery disease
• severe valvular disease
• Refuses to sign an consent form after having received the appropriate information
• Refuses to co-operate
• Not able to understand the study objectives and protocol
• Not available for scheduled follow-up
• With a life expectancy less than one year
• Already included into another clinical study competing with the objectives of the CAN-SAVE R study.
• <18 years old.

Contraindications Any patient to whom a contraindication from device labeling applies shall not be included in the study.

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Study Plan

How is the study designed?

Design Details

• Primary Purpose: TREATMENT
• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: SINGLE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
ACTIVE_COMPARATOR: DDD Long AVD	Procedure: Symphony Dual Chamber Rate Responsive Device; Echocardiography ANP/BNP measurements
EXPERIMENTAL: safeR	Procedure: Symphony Dual Chamber Rate Responsive Device; Echocardiography ANP/BNP measurements

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Percentage of ventricular pacing
Atrial Fibrillation/Atrial Arrhythmia Evolution
Cardiac Function Evolution

Secondary Outcome Measures

Outcome Measure
Congestive Hear Failure and Atrial Fibrillation Clinical Events
Evolution of conduction Disturbances
Safety Analysis

Collaborators and Investigators

• Sponsor: Sorin Group Canada
• Investigators: Principal Investigator: Bernard Thibault, MD, IntMed,Cardiologist, Institute de Cardilogie Montreal, Montreal Hear t Institute

Publications and helpful links

General Publications

• Thibault B, Simpson C, Gagne CE, Blier L, Senaratne M, McNicoll S, Stuglin C, Williams R, Pinter A, Khaykin Y, Nitzsche R. Impact of AV conduction disorders on SafeR mode performance. Pacing Clin Electrophysiol. 2009 Mar;32 Suppl 1:S231-5. doi: 10.1111/j.1540-8159.2008.02293.x.
• Thibault B, Ducharme A, Baranchuk A, Dubuc M, Dyrda K, Guerra PG, Macle L, Mondesert B, Rivard L, Roy D, Talajic M, Andrade J, Nitzsche R, Khairy P; CAN-SAVE R Study Investigators. Very Low Ventricular Pacing Rates Can Be Achieved Safely in a Heterogeneous Pacemaker Population and Provide Clinical Benefits: The CANadian Multi-Centre Randomised Study-Spontaneous AtrioVEntricular Conduction pReservation (CAN-SAVE R) Trial. J Am Heart Assoc. 2015 Jul 23;4(7):e001983. doi: 10.1161/JAHA.115.001983.

Study record dates

Study Major Dates

• Study Start: April 1, 2006
• Primary Completion (ACTUAL): April 1, 2009
• Study Completion (ACTUAL): April 1, 2009

Study Registration Dates

• First Submitted: October 12, 2010
• First Submitted That Met QC Criteria: October 12, 2010
• First Posted (ESTIMATE): October 13, 2010

Study Record Updates

• Last Update Posted (ESTIMATE): October 13, 2010
• Last Update Submitted That Met QC Criteria: October 12, 2010
• Last Verified: September 1, 2006

More Information

Terms related to this study

• Keywords: Symphony DR 2550,; Dual Chamber Pacemaker,; Sorin,; Ela Medical,; DDD Mode,; AAIsafeR2 mode,; AV-Conduction,; Reducing Ventricular Pacing,; Congestive Heart Failure,; Cardiac Function,; Atrial Arrhythmia,; Atrial Fibrillation,; Atrial and Ventricular Hemodynamics,; Long AV-delays.; Ventricular Function,; Implantation,
• Other Study ID Numbers: IGXD04