Patient Selection and Long-Term Outcomes of Pace & Ablate Strategy in Atrial Fibrillation (REPACE)

Patient Selection and Long-Term Outcomes in Patients With a Pace & Ablate Strategy for Interventional Rate Control in Symptomatic Permanent Atrial Fibrillation - A Retrospective Multicenter Analysis

Atrioventricular node ablation with permanent pacing (the "pace-and-ablate" strategy) controls ventricular rate in atrial fibrillation that has not responded to drug therapy or catheter ablation. Chronic right ventricular pacing, however, can cause pacing-induced cardiomyopathy (PICM), and it is not well established which patients are at risk and should therefore receive conduction system pacing or biventricular pacing instead.

REPACE is a multicentre retrospective cohort of consecutive patients who underwent atrioventricular node ablation from January 2011 onwards at five centres in Switzerland, the United Kingdom and Poland: Liverpool Heart and Chest Hospital, Inselspital Bern, University Hospital Basel, Geneva University Hospitals and the Silesian Centre for Heart Diseases, Zabrze. More than 2,000 patients ablated up to March 2024 have been included to date; patients ablated after that date at the participating centres are being added.

The study has three aims: to validate, in an independent multicentre population, a previously published risk model for pacing-induced cardiomyopathy; to describe the procedural technique and outcomes of atrioventricular node ablation across different health systems; and to estimate the health-economic impact of the pace-and-ablate strategy.

Pacing-induced cardiomyopathy is defined as an absolute reduction in left ventricular ejection fraction of at least 10 percentage points to a value below 50%. All potential endpoints are adjudicated by a clinical events committee blinded to the classification made at the site.

Study Overview

• Status: Recruiting
• Conditions: Heart Failure; Pacing-Induced Cardiomyopathy; Atrial Fibrillation (AF); Cardiomyopathy, Secondary

Detailed Description

Data collection. Baseline demographics, comorbidity, device and procedural data, electrocardiographic and echocardiographic measurements, follow-up events and mortality were abstracted from hospital records at each participating centre into a central electronic case report form.

Endpoint adjudication. Every potential endpoint is reviewed by two independent adjudicators blinded to the classification made at the site, with a third reviewer consulted where they disagree. Pacing-induced cardiomyopathy is assessed on every adjudicated event, independently of how that event is otherwise classified.

Analysis populations. The validation of the risk model is performed in the patients who had neither cardiac resynchronisation therapy nor conduction system pacing at baseline, because a decline in left ventricular function in an already resynchronised patient represents non-response to resynchronisation rather than pacing-induced cardiomyopathy. Patients with resynchronisation at baseline are described and contribute to the procedural and health-economic analyses. No lower limit of baseline ejection fraction is applied: since the definition requires a fall of at least 10 percentage points to a value below 50%, patients already below 50% at baseline can meet it.

Health-economic analysis. Direct costs are derived from Hospital Episode Statistics in the United Kingdom, individual procedure costs from the SwissEPnet registry for Switzerland, and diagnosis-related group and hospital costs for Switzerland and Poland, covering hospital charges, device costs and subsequent care for complications and follow-up. Cost-utility and cost-effectiveness analyses use Markov models to compare pacing strategies.

• Study Type: Observational
• Enrollment (Estimated): 2600

Contacts and Locations

• Study Contact: Name: Nikola A Kozhuharov, PD Dr. med.; Phone Number: +41 76 443 90 86; Email: nikola.kozhuharov@insel.ch

Study Locations

• Poland
  • Zabrze, Poland, 41-800
    • Recruiting
    • Silesian Centre for Heart Diseases
    • Principal Investigator: Agnieszka Babińska, MD
• Switzerland
  • Basel, Switzerland, 4031
    • Recruiting
    • University Hospital Basel
    • Principal Investigator: Christian Sticherling, MD
  • Geneva, Switzerland, 1205
    • Recruiting
    • Geneva University Hospitals
    • Principal Investigator: Haran Burri, MD
  • Canton of Bern
    • Bern, Canton of Bern, Switzerland, 3010
      • Recruiting
      • Inselspital, Universitätsspital Bern
      • Contact: Nikola A Kozhuharov, PD Dr. med.; Email: nikola.kozhuharov@insel.ch
      • Principal Investigator: Nikola A Kozhuharov, PD Dr. med.
• United Kingdom
  • Merseyside
    • Liverpool, Merseyside, United Kingdom, L14 3PE
      • Recruiting
      • Liverpool Heart and Chest Hospital
      • Contact: Dhiraj Gupta, MD, FRCP; Email: Dhiraj.Gupta@lhch.nhs.uk
      • Principal Investigator: Dhiraj Gupta, MD, FRCP

Participation Criteria

Eligibility Criteria

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

• Sampling Method: Non-Probability Sample

Study Population

Consecutive adults with symptomatic atrial fibrillation refractory to drug therapy or catheter ablation who underwent atrioventricular node ablation as part of a pace-and-ablate strategy at five participating centres in Switzerland, the United Kingdom and Poland from January 2011 onwards.

Retrospective inclusion is covered by general consent to the further use of health-related data where this is on file. For deceased or uncontactable patients with no documented refusal, inclusion is covered by the exception from consent under Article 34 of the Swiss Human Research Act (Absence of informed consent), the project having been approved by the Kantonale Ethikkommission Bern. The United Kingdom site operates under IRAS 314643.

Description

Inclusion Criteria:

• Age 18 years or older at the time of atrioventricular node ablation
• Atrial fibrillation, undergoing atrioventricular node ablation with a permanent cardiac implantable electronic device already in situ or implanted as part of the pace-and-ablate strategy
• Availability of baseline echocardiographic data, including left ventricular ejection fraction

Exclusion Criteria:

* Documented refusal of the further use of health-related data

Note: cardiac resynchronisation therapy or conduction system pacing at baseline is not an eligibility exclusion. Such patients are included in the cohort and in the procedural and health-economic analyses, but are excluded from the validation of the pacing-induced cardiomyopathy risk model, in which a decline in left ventricular function would represent non-response to resynchronisation. No lower limit of baseline ejection fraction is applied.

Study Plan

How is the study designed?

Design Details

• Observational Models: COHORT
• Time Perspectives: RETROSPECTIVE

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Pace-and-ablate cohort; Consecutive adults with atrial fibrillation who underwent atrioventricular node ablation with a permanent cardiac implantable electronic device at the five participating centres from January 2011 onwards. Within this cohort, the patients who had neither cardiac resynchronisation therapy nor conduction system pacing at baseline form the population for the validation of the pacing-induced cardiomyopathy risk model.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of pacing-induced cardiomyopathy (PICM)	Proportion of patients who develop PICM, defined as an absolute reduction in left ventricular ejection fraction (LVEF) of at least 10 percentage points to a value below 50% on echocardiography after atrioventricular node ablation with ventricular pacing. Each potential event is adjudicated by two independent reviewers blinded to the classification made at the site, with a third reviewer consulted in case of disagreement.	From atrioventricular node ablation up to 10 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
All-cause mortality by pacing modality	Proportion of patients who die from any cause, reported separately for right ventricular pacing, biventricular pacing and conduction system pacing.	From atrioventricular node ablation up to 5 years
Heart failure hospitalisation by pacing modality	Proportion of patients with at least one hospitalisation for heart failure, reported separately for right ventricular pacing, biventricular pacing and conduction system pacing.	From atrioventricular node ablation up to 5 years
Acute procedural success of atrioventricular node ablation	Proportion of procedures with complete atrioventricular block at the end of the procedure, i.e. intended loss of atrioventricular conduction with transition to ventricular pacing.	Periprocedural (index atrioventricular node ablation)
Use of a second ablation catheter, by type of first ablation catheter (irrigated versus non-irrigated)	Proportion of procedures in which a second ablation catheter was required to achieve atrioventricular block, reported separately for procedures started with an irrigated and with a non-irrigated catheter.	Periprocedural (index atrioventricular node ablation)
Presence of a ventricular escape rhythm after atrioventricular node ablation	Proportion of patients with a ventricular escape rhythm documented at the end of the atrioventricular node ablation procedure.	Periprocedural (index atrioventricular node ablation)
Procedure duration by use of a long sheath	Duration of the atrioventricular node ablation procedure in minutes, reported separately for procedures performed with and without a long sheath.	Periprocedural (index atrioventricular node ablation)
Cumulative direct healthcare costs per patient	Cumulative direct healthcare costs per patient in euros, covering the index procedure (hospital stay, device and consumables) and subsequent hospital care for complications and follow-up. Costs are derived from Hospital Episode Statistics (United Kingdom), the SwissEPnet registry and diagnosis-related group data (Switzerland, Poland) and converted to euros.	From atrioventricular node ablation up to 5 years
Incremental cost-effectiveness ratio of conduction system pacing versus right ventricular pacing	Incremental cost per quality-adjusted life-year (QALY) gained, estimated with a Markov model from the observed event rates and direct healthcare costs, overall and across strata of predicted pacing-induced cardiomyopathy risk and of procedural complexity.	From atrioventricular node ablation up to 5 years
Return to sinus rhythm during follow-up	Proportion of patients with documented return to sinus rhythm on electrocardiogram or device interrogation after atrioventricular node ablation.	From atrioventricular node ablation up to 5 years
Discrimination of the published and of an updated pacing-induced cardiomyopathy risk model (C-statistic)	C-statistic (area under the receiver operating characteristic curve) for predicting pacing-induced cardiomyopathy, reported for the previously published risk model as originally specified and for a model updated in this cohort (recalibration and re-estimation of predictor weights, with candidate additional predictors), in patients without cardiac resynchronisation therapy or conduction system pacing at baseline.	From atrioventricular node ablation up to 10 years
Incremental cost-effectiveness ratio of biventricular pacing versus right ventricular pacing	Incremental cost per quality-adjusted life-year (QALY) gained, estimated with a Markov model from the observed event rates and direct healthcare costs, overall and across strata of predicted pacing-induced cardiomyopathy risk and of procedural complexity.	From atrioventricular node ablation up to 5 years

Collaborators and Investigators

• Sponsor: Insel Gruppe AG, University Hospital Bern
• Collaborators: University Hospital, Geneva; University Hospital, Basel, Switzerland; University of Bern; Liverpool Heart and Chest Hospital NHS Foundation Trust; Silesian Centre for Heart Diseases, Zabrze
• Investigators: Principal Investigator: Nikola A Kozhuharov, PD Dr. med., Insel Gruppe AG, University Hospital Bern

Publications and helpful links

General Publications

• Kozhuharov N, Gstoehl AM, Calvert P, Koniari I, Najm A, Mills MT, Thu K, Xydis P, Usteri R, Babinska A, Haeberlin A, Reichlin T, Sticherling C, Burri H, Wright DJ, Rao A, Gupta D. Predictors of pacing-induced cardiomyopathy in patients undergoing AV nodal ablation: insights from a Delphi process and retrospective cohort study. Eur Heart J Open. 2026 Jun 29;6(3):oeag102. doi: 10.1093/ehjopen/oeag102. eCollection 2026 May.

Study record dates

Study Major Dates

• Study Start (Actual): January 5, 2011
• Primary Completion (Estimated): June 30, 2027
• Study Completion (Estimated): December 31, 2027

Study Registration Dates

• First Submitted: September 8, 2026
• First Submitted That Met QC Criteria: September 25, 2026
• First Posted (Actual): October 1, 2026

Study Record Updates

• Last Update Posted (Actual): October 1, 2026
• Last Update Submitted That Met QC Criteria: September 25, 2026
• Last Verified: September 1, 2026

More Information

Terms related to this study

• Keywords: Conduction system pacing; Atrioventricular node ablation; Pace-and-ablate
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Pathologic Processes; Heart Diseases; Arrhythmias, Cardiac; Pathological Conditions, Signs and Symptoms; Heart Failure; Atrial Fibrillation; Cardiomyopathies
• Other Study ID Numbers: 2019-01151; 2019 (U.S. NIH Grant/Contract); 4079 (Other Identifier: Insel Gruppe AG, University Hospital Bern); 314643 (Other Identifier: IRAS, UK Health Research Authority)

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No