CRT and AVN ablation in AF
Research type
Research Study
Full title
Cardiac Resynchronisation Therapy (CRT) and AV Node ablation trial in Atrial Fibrillation (CAAN-AF)
IRAS ID
243344
Contact name
Matthew G D Bates
Contact email
Sponsor organisation
SAHMRI South Australian Health and Medical Research Institute
Clinicaltrials.gov Identifier
Duration of Study in the UK
4 years, 0 months, 1 days
Research summary
Heart failure (HF) is an important worldwide health problem causing significant morbidity and mortality. 20% of patients with HF have uncoordinated heart muscle worsening pump function. Cardiac Resynchronisation Therapy (CRT) is a important treatment in these patients, using a complex pacemaker to coordinate the heart and improve pump function, symptoms and prognosis.
Almost all CRT studies have excluded HF patients who also have an irregular pulse, known as atrial fibrillation (AF). 25% of patients with HF will also have AF. Small studies of CRT in HF patients with AF have shown very variable results and a often a complete lack of response to CRT. We do not know why this happens. CRT may not be able to achieve enough coordination of the heart in HF patients with AF. There is a pressing need to study specific interventions that may extend the benefits of CRT to HF patients with AF.
There is evidence in patients with normal heart rhythm and CRT that the response to CRT is critically linked to the amount of CRT pacing that can be achieved (targeting 100% CRT pacing). AV nodal (AVN) ablation is a simple procedure that will ensure 100% CRT pacing in patients with AF by preventing any conducted beats. AVN ablation has been suggested in HF patients with AF but acceptance has been limited because AVN ablation results in patients becoming dependent on their pacemaker. Current practice amongst heart specialists is variable with regard to AVN ablation use in HF patients with CRT and AF.
Small observational studies suggests that AVN ablation may benefit HF patients with CRT and AF. CAAN-AF is a randomised controlled trial of AVN ablation and medical therapy in patients with HF and AF. If it helps HF patients with CRT and AF, AVN ablation could soon become part of normal treatment.
REC name
North East - Newcastle & North Tyneside 2 Research Ethics Committee
REC reference
19/NE/0362
Date of REC Opinion
8 Jan 2020
REC opinion
Further Information Favourable Opinion