Rate Control Therapy Evaluation in Permanent Atrial Fibrillation (RATE-AF) (RATE-AF)
Atrial fibrillation is a common heart rhythm disturbance, causing important discomfort for patients, a high risk of stroke, frequent hospital admissions and a two-fold increase in death. The number of patients with this condition are expected to double in the next 20 years. Medications to control heart-rate are used in the majority of patients, although the choice of agent is often guided by local preference rather than evidence from controlled trials. Despite the fact that patients with atrial fibrillation have high rates of other cardiac conditions such as heart failure, clinicians have insufficient evidence to personalise the use of different therapies. This feasibility study will allow us to develop a range of methods that can characterise patients according to the pumping and relaxing function of the heart, the burden of symptoms and to identify new blood markers. In this way, the investigators hope to improve clinical practice guidelines, allowing doctors to prescribe appropriate treatments for the right patients.
The research will be focused around a randomised trial of two medication strategies, providing much-needed data on the comparison of digoxin and beta-blockers (two commonly-used drugs in patients with atrial fibrillation). It will also allow us to identify the best way to record patient-reported quality of life and develop robust techniques to determine heart function using non-invasive imaging, facilitating the conduct of a large-scale clinical trial. The key objectives of the research programme are to define the optimal medications for patients with atrial fibrillation and identify the most valid, reproducible and cost-effective methods to examine patients. The ultimate aim of the project is to improve clinical outcomes in atrial fibrillation, benefiting patients, the National Health Service and the global community.
|Study Design:||Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Treatment
|Official Title:||Evaluating Different Rate Control Therapies in Permanent Atrial Fibrillation: A Prospective, Randomised, Open-label, Blinded Endpoint Feasibility Pilot Comparing Digoxin and Beta-blockers as Initial Rate Control Therapy|
- Patient reported quality of life (SF-36) [ Time Frame: 12 months ]
Patient-reported outcomes at 6 months as assessed by the SF-36 questionnaire physical component score.
Detailed QoL outcomes will be determined during the pilot study. Anticipated patient-reported outcomes include AFEQT and the physical functioning subset of SF-36, with EQ-5D-5L for health-economic evaluation. We will identify appropriate and responsive patient-reported outcomes from a variety of quality of life questionnaires, including qualitative research with individual patients to assess levels of missing data, patient acceptability and optimum delivery methods.
- Left ventricular ejection fraction [ Time Frame: 12 months ]The above parameters will be measured using echocardiography and diastolic indices
- Diastolic function [ Time Frame: 12 months ]The above parameters will be measured using echocardiography and diastolic indices
- B-type natriuretic peptide (BNP) [ Time Frame: 6 months ]Change in BNP levels as a surrogate for total ventricular strain, at 6 months
- Composite functional status measures [ Time Frame: 12 months ]Change in 6 minute walking distance achieved at 6 and 12 month timepoints and change in European Heart Rhythm Association (EHRA)/New York Heart Association (NYHA) class at same timepoints
- Patient reported outcomes [ Time Frame: 12 months ]As assessed using the AFEQT overall score at both 6 and 12 months
- Patient reported outcomes [ Time Frame: 12 months ]As assessed using the SF-36 global and specific scores at both 6 and 12 months
- Patient reported outcomes [ Time Frame: 12 months ]As assessed using the EQ-5D-5L summary index and visual analogue scale questionnaires at both 6 and 12 months
- Change in heart-rate from baseline [ Time Frame: 12 months ]Change in heart rate using ambulatory monitoring at 12 month timepoint
- Cardiovascular events [ Time Frame: 12 months ]Measured by hospital admissions for these events
- Drug discontinuation rate [ Time Frame: 12 months ]the number and extent to which patients discontinue trial drugs
- Frequency and nature of adverse reactions [ Time Frame: 12 months ]Frequency and nature of adverse reactions
- Hospital admission rate [ Time Frame: 12 months ]A composite of adverse clinical events
- Retention of participants [ Time Frame: 12 months ]Convenience, compliance and cross-over data
- Preferred outcome measures for this cohort of patients [ Time Frame: 12 months ]Establish which are the best measures for these patients
- Population-specific standard deviations to enable sample size calculation for a future trial powered to detect a difference in hospital admissions. [ Time Frame: 12 months ]SF-36 physical function score at 6 and 12 months
- Population-specific standard deviations to enable sample size calculation for a future trial powered to detect a difference in hospital admissions. [ Time Frame: 12 months ]SF-36 overall score at 6 and 12 months
- Population-specific standard deviations to enable sample size calculation for a future trial powered to detect a difference in hospital admissions. [ Time Frame: 12 months ]AFEQT overall score at 6 and 12 months
- Population-specific standard deviations to enable sample size calculation for a future trial powered to detect a difference in hospital admissions. [ Time Frame: 12 months ]LVEF and E/e scores at 6 and 12 months
- Population-specific standard deviations to enable sample size calculation for a future trial powered to detect a difference in hospital admissions. [ Time Frame: 12 months ]unplanned hospital admission rates
|Study Start Date:||July 2016|
|Estimated Study Completion Date:||July 2019|
|Estimated Primary Completion Date:||July 2018 (Final data collection date for primary outcome measure)|
Active Comparator: Beta-blocker
In Group B, oral bisoprolol will be commenced at either 1.25mg, 2.5mg or 5mg according to the treatment schedule and uptitrated, as required, to 15mg daily. Recommended additional therapy in this arm includes diltiazem. Use of digoxin is explicitly discouraged but will not terminate participation in the study. If intolerance to bisoprolol occurs, investigators will be advised to try an alternate beta-blocker of their choosing (typically carvedilol, nebivolol, or metoprolol) at equivalent dosage.
Active Comparator: Digoxin
In Group A, the maintenance dose of oral digoxin will be either 62.5mcg or 125mcg according to the pre-defined treatment schedule and uptitrated, as required, to 250mcg daily. A single loading dose of four tablets (250 or 500mcg according to target maintenance dose) will be prescribed in digoxin-naïve participants, where necessary. Recommended additional therapy in this arm includes the calcium-channel blocker diltiazem. Use of beta-blockers is explicitly discouraged but will not terminate participation in the study.
Atrial fibrillation (AF) is an increasingly common cardiac condition that leads to a substantial burden on quality-of-life (QoL), an increased risk of cardiovascular events, hospitalisation and death, and significant healthcare costs for the NHS. In addition to anti-coagulation and considerations for rhythm control therapy, most patients with AF are in need of pharmacological control of heart rate. This aspect of care has not received stringent investigation, with treatment guidelines based on small crossover studies and observational data rather than robust controlled trials. Beta-blocker monotherapy remains the first-line option in the current NICE AF guidelines consultation document, with digoxin only for sedentary patients, although this recommendation is based on 'very low-quality evidence'. The benefit of different rate-control therapies on symptoms and other intermediate outcomes (such as left-ventricular ejection fraction [LVEF] and diastolic function) are unknown, as are their effects on clinical events such as hospitalisation. This situation is unacceptable in light of the potential benefits and risk of different rate-control options in AF. It also limits our ability to personalise treatment according to patient characteristics.
The RAte control Therapy Evaluation in permanent Atrial Fibrillation (RATE-AF) trial is informed by a number of in-depth systematic reviews of management and clinical outcomes in AF patients. Taken together, this information provides a sound basis to plan a major randomised controlled trial (RCT). However as trials of rate-control in AF have typically been small or uncontrolled, further information is needed before designing a trial that can assess clinical outcomes. The RATE-AF trial will allow us to define appropriate primary and secondary outcome measures and their standard deviation in a contemporary population of patients with permanent AF. This information will allow us to estimate sample size, determination of recruitment, retention and adherence policies, and to ascertain the best methods of obtaining adverse event data and reliable economic costs for a larger trial assessing cardiovascular outcomes and hospitalization. The RATE-AF trial will also be the largest RCT of its kind, allowing us to compare the effect of beta-blockers and digoxin on QoL as initial rate-control therapy in patients with permanent AF. The long-term aim of the research is to answer key questions about how to initiate therapy, stratified by relevant patient characteristics such as systolic and diastolic cardiac function, baseline symptoms and concurrent medication. The research will also define the patho-physiological mechanisms underlying AF-related symptoms, left-ventricular function and their association with adverse clinical outcomes, and to identify clinical markers for the response to different rate control therapy.
Please refer to this study by its ClinicalTrials.gov identifier: NCT02391337
|Contact: Dipak Kotecha, MBChB PhD MRCPfirstname.lastname@example.org|
|City Hospital||Not yet recruiting|
|Birmingham, West Midlands, United Kingdom|
|Queen Elizabeth Hospital||Not yet recruiting|
|Birmingham, West Midlands, United Kingdom|
|Principal Investigator:||Dipak Kotecha, MBChB PhD MRCP||University of Birmingham|