Objective Randomised Blinded Investigation of Cardioversion Versus Ablation for Persistent Atrial Fibrillation (ORBICA-AF)
Overview
- Phase
- Not Applicable
- Intervention
- Not specified
- Conditions
- Persistent Atrial Fibrillation
- Sponsor
- Barts & The London NHS Trust
- Enrollment
- 208
- Locations
- 1
- Primary Endpoint
- Recurrence of Persistent AF (AF episode lasting > 7 days) or left atrial ablation/ DC Cardioversion for atrial arrhythmia after 6 weeks of blanking period.
- Status
- Recruiting
- Last Updated
- 8 months ago
Overview
Brief Summary
The main aim of the research is to investigate whether patients undergoing pulmonary vein isolation with catheter ablation for persistent atrial fibrillation (AF) will have lower rates of AF recurrence than those treated by DC cardioversion without an ablation procedure.
Detailed Description
After adequate stroke prevention (e.g. anticoagulation) and rate control, the optimum strategy for patients who continue to be symptomatic with persistent AF has not been established. Cardioversion with antiarrhythmic medication is commonly used as a first-line rhythm control strategy despite very high recurrence rates of index arrhythmia and high serious complications associated with this strategy. Further treatment options, such as catheter ablation or implantation of a pacemaker and ablation of the atrioventricular (AV) node, are considered once AF recurs. The benefits of first-line ablation in patients presenting with persistent AF have not been tested. Investigators seek to perform a blinded, randomised trial comparing an electrical cardioversion-led strategy with a pulmonary-vein isolation strategy for the treatment of persistent atrial fibrillation. No blinded randomised controlled trial comparing early-ablation strategies to cardioversion-led strategies has been performed. The rationale for blinding where possible in clinical trials is well established. The recently published ORBITA trial performed a blinded, multicentre randomised trial of percutaneous coronary intervention (PCI) in stable angina compared to a placebo procedure. This trial demonstrated that the efficacy of invasive procedures can be assessed with a placebo procedure and that this type of trial remains necessary. Knowledge of treatment assignment influences physician behaviour, drug recommendations and encourages bias in outcome reporting. The treatment effect size and the effects of confounding factors will be exaggerated and thus limit the interpretation of the true patient-experienced outcomes of either strategy. In a comparison of surgical procedures, a sham control arm represents the gold standard of blinding. A systematic review of placebo-controlled surgical trials found no evidence of harm to participants assigned to the placebo group. For a procedure whose primary purpose is to give sustained symptomatic relief, definitive quantification of the true placebo-controlled effect size of AF ablation is necessary. There is a need to clarify the relationship between patient-reported symptoms and the arrhythmia itself. Patient-reported symptoms may not always be related to the severity of the arrhythmia or quality of life. No bias-resistant blinded, randomised, trial has yet been performed seeking to measure the benefits of AF ablation in persistent AF. The investigators of this trial have achieved successful recruitment and concluded the pilot phase (ORBITA AF trial; ClinicalTrials.gov Identifier: NCT03907982) with the goal of assessing feasibility and optimizing the study protocol prior to conducting a larger trial. The positive outcomes of the pilot phase have paved the way for this larger follow-on trial.
Investigators
Eligibility Criteria
Inclusion Criteria
- •Ability to give informed consent
- •Age 18-85 years
- •Persistent AF (atrial fibrillation lasting \> 7days) of total continuous duration \<2 years as documented in medical notes.
- •Patients being considered for cardioversion.
Exclusion Criteria
- •Creatinine clearance (eGFR) \< 30mls/min
- •Contraindication or unable to take anticoagulation
- •Uncontrolled hypertension
- •Contraindication for catheter ablation
- •BMI \> 40
- •Patients in Persistent AF who have had more than one previous cardioversion.
- •Established diagnosis of Hypertrophic cardiomyopathy
Outcomes
Primary Outcomes
Recurrence of Persistent AF (AF episode lasting > 7 days) or left atrial ablation/ DC Cardioversion for atrial arrhythmia after 6 weeks of blanking period.
Time Frame: Within 12 months following the procedure
Rates of recurrence of arrhythmia and data on episodes of Atrial Fibrillation (rate, duration) will be provided by the loop recorder, and downloaded via a home monitoring system \[ rhythm on ILR ECG\]
A change in the burden of AF, as measured by continuous monitoring through ILR (Implantable loop recorder) at 3 months
Time Frame: 3 months post randomisation
Percentage time the patient is in AF as measured by the ILR device (in percentage) compared to pre-randomisation
Secondary Outcomes
- Bleeding events(Within 7 days of the index procedure)
- Change in quality of life measures using Atrial Fibrillation Effect on QualiTy-of-life(AFEQT) questionnaire(Between baseline and 3, 6 and 12 months after procedure)
- The occurrence of atrial tachyarrhythmias(Within 12 months following the index procedure)
- Composite adverse events(12 months)
- Rates of Subject Hospital re-admission(Within 12 months of study index procedure.)
- Cardiac function(between baseline and 12 months following the procedure)
- Antiarrhythmic drug use(Between baseline and 12months after procedure)
- Death(Within 12 months of study index procedure.)
- Procedural complications(Up to 7 days post procedure)
- Percentage of clinical success of procedure(Within 12 months following the index procedure)
- Change in quality of life score using in 12 item Short Form health survey (SF12)(Between baseline and 3, 6 and 12 months after procedure)
- Measuring AF Burden(At 3, 6 and 12 months follow up)
- Rates of Repeat procedures(within 12 months following the procedure)
- Symptomatic Atrial fibrillation/Atrial tachycardia episodes(At 3, 6, 12 months follow up)
- Measuring Blinding index(Day 0 (within 24 hours post randomisation) and 3 months)