Investigation of Therapeutic Ablation Versus Cardioversion for AF

Not Applicable

Completed

Conditions: Persistent Atrial Fibrillation
Cardiac Arrhythmia

Registration Number: NCT03907982

Lead Sponsor: Barts & The London NHS Trust

Brief Summary: The main aim of the research is to investigate whether patients undergoing pulmonary vein isolation with cryoablation for atrial fibrillation (AF) will have lower rates of AF recurrence than those treated by DC cardioversion without an ablation procedure. The objectives of the Pilot Study are to validate the key study logistics with a view to optimising methods to be used in the main study.

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 the 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 has not been tested. We 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 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.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 20

Inclusion Criteria

Patients who meet the following inclusion criteria will be eligible for the study;

Ability to give informed consent
Age 18-80 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

Patients who meet the following exclusion criteria will be ineligible for study participation;

Creatinine clearance (eGFR) < 30mls/min
Contraindication or unable to take anticoagulation
Known contraindication to or unable to tolerate amiodarone
Uncontrolled hypertension
Contraindication to catheter ablation
BMI > 35

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Recurrence of Persistent AF (of AF Episode Lasting > 7 Days).	Within 12 months following the procedure	Data on epsiodes of Atrial Fibrillation (rate, duration) will be provided by the loop recorder, and downloaded via a home monitoring system

Secondary Outcome Measures

Name	Time	Method
Bleeding Events	Within 7 days of the procedure	Rates of bleeding in subjects following the study DCCV +/- pulmonary vein isolation (PVI) procedures
Death	Within 12 months of study recruitment	Death of the patient
Rates of Subject Hospital Re-admission	Within 12 months following the procedure	Rates of admission of the subject back to hospital following the initial treatment for AF
Procedural Complications	At the time of the procedure	Assessment of rates of events that are considered procedural complications during the DCCV +/- Pulmonary Vein isolation (PVI) procedure
Rates of Repeat Procedures	within 12 months following the procedure	Requirement for repeat procedures following the initial DCCV +/- pulmonary vein isolation (PVI) procedure for the study
Clinical Success of Procedure	Within 12 months following the procedure	Clinical procedural success as defined by 75% or greater reduction in the number of AF episodes as measured by the insertable cardiac monitoring system (LINQ) device.
Change in Quality of Life Measures (Using Short Form-12 Survey)	Between baseline and 12 months after procedure	Assessment of quality of life measures using Short Form Health Survey (SF12) questionnaire, which is a multipurpose short form survey with 12 questions, all selected from the SF-36 Health Survey (Ware, Kosinski, and Keller, 1996). The questions are combined, scored, and weighted to create two scales that provide glimpses into mental and physical functioning and overall health-related-quality of life. Scale range from 0 to 100, with higher scores indicating better quality of life.
Change in Quality of Life Measures (AF-PROMS)	between baseline and 12 months after procedure	Assessment of Patient Reported Outcome Measures (PROMS) specific for Atrial Fibrillation (AF) in a series of 28 questions to assess the impact of AF on the subject's quality of life. Atrial Fibrillation Severity Scale (AFSS) uses a scale ranging from 0 to 35, where a higher score indicates more severe symptoms.

Trial Locations

Locations (1): Barts Health NHS Trust - St Bartholomew's Hospital and Whipps Cross Hospital
🇬🇧
London, United Kingdom
Barts Health NHS Trust - St Bartholomew's Hospital and Whipps Cross Hospital
🇬🇧London, United Kingdom