None listed
Conditions
Brief summary
Atrial fibrillation (AF) is an irregular heart rhythm that is common and is associated with impaired heart function, stroke and increased risk of hospitalisation or death. Aldosterone and other substances that activate mineralocorticoid receptors usually play a role in maintaining blood pressure and blood volume, but recent evidence suggest that they may also contribute to the development of AF. The proposed study will test whether blockade of mineralocorticoid receptors with an oral medication called spironolactone that is already proven to be beneficial for subjects with heart failure, can also reduce AF in subjects who already have a cardiac pacemaker. Using the cardiac pacemaker will allow more accurate detection of the total number and duration of episodes of AF. Participants in the study will receive either daily spironolactone or placebo tablets for 18 months and the difference in number of AF episodes will be identified from pacemaker recordings
Interventions
We will test the ability of the oral mineralocorticoid receptor antagonist (MRA), spironolactone, to prevent Atrial Fibrillation (AF) by performing a randomised controlled clinical trial and using monitoring features of implanted pacemakers to accurately document AF. Participants will be randomised 1:1 to receive either placebo or spironolactone 50mg per day for 18 months.
The dose of the study drug will be adjusted by the study doctor every 3 months during the 18 month intervention period acc
We will test the ability of the oral mineralocorticoid receptor antagonist (MRA), spironolactone, to prevent Atrial Fibrillation (AF) by performing a randomised controlled clinical trial and using monitoring features of implanted pacemakers to accurately document AF. Participants will be randomised 1:1 to receive either placebo or spironolactone 50mg per day for 18 months. The dose of the study drug will be adjusted by the study doctor every 3 months during the 18 month intervention period according to renal function (eGFR) and potassium (K+) biochemistry levels. . The starting drug dose will be 25mg/d, titrated to 50mg/d after 4 weeks if K+ is <5mmol/L If the baseline eGFR is 30-50ml/min/1.73m2, the starting dose will be 25mg on alternate days and titrated to 25mg daily at 4 weeks if K+ <5mmol/L The dose will be halved if K+ increases into the range 5.5 - 6mmol/L or eGFR falls <15ml/min/1.73m2. Following dose reduction, blood tests will be repeated K+ / eGFR in 72hrs and doses continued if K+ <5 and eGFR >30ml/min/1.73m2 Study drug withheld if K+>6mmol/L, restart at half dose only if K+<5mmol/L at 72hrs Study drug withheld if eGFR <15ml/min/1.73m2 and restarted once eGFR > 30ml/min/1.73m2 Medications will be counted as a check on adherence at all study visits.
Sponsors
University of Otago
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Prevention
Masking
Blinded (masking used) (Subject, Caregiver, Outcomes Assessor)
Eligibility
Sex/Gender
All
Age
19 Years to No maximum
Healthy volunteers
No
Inclusion criteria
Patients with an implanted cardiac device capable of recording the frequency and duration of AF events and with evidence of AF or AHRE within the 6months prior to recruitment will be eligible. Inclusion criteria: age >18 years (without childbearing potential for women); with an implantable device capable of AF or AHRE monitoring; and with device documented AF or AHRE (defined as AHRE >220 bpm for >2% of the time or for > 5mins on at least one occasion) in the last 6months.
Exclusion criteria
Permanent AF, Receiving AF suppression pacing History of heart failure with indication for MRAs A clinical indication for MRA or K+ sparing diuretic Contraindication to MRA Severe renal dysfunction Sustained hyperkalaemia in the absence of reversible cause
Outcome results
None listed