Protocol - Understanding the acceptability of opportunistic identification of undiagnosed and untreated atrial fibrillation during unscheduled contact with emergency ambulance services: a qualitative exploration

Atrial fibrillation (AF) is a common heart rhythm disturbance, or arrhythmia. It causes the heart to beat abnormally and is a significant risk factor for stroke. Taking oral anticoagulant (blood thinning) medications substantially reduces the risk of stroke in people diagnosed with AF.  It is estimated that 400,000 people in England have undiagnosed and therefore untreated AF, leaving them at increased risk of stroke. Sometimes people don't experience any symptoms and AF gets detected incidentally during a routine clinical test or scheduled examination. Formalising such opportunities for finding undiagnosed AF could lead to more timely prescription of anticoagulant medication and a subsequent reduction in avoidable strokes. AF can be detected by electrocardiogram (ECG), which is a simple heart trace. Emergency medical services (EMS) ambulance crews encounter a wide range of people on a daily basis and perform detailed routine assessments that often include an ECG.  Whilst most patients attended by EMS are conveyed to hospital for further medical assessment, investigations and treatment, many patients are treated at the scene by EMS staff and remain in the community.  This group provides a novel opportunity to screen for hidden cardiovascular risk factors.  Whilst pilot work by the authors estimates that many people could benefit, it is important to understand the acceptability and feasibility of identifying AF in this way from the perspective of those giving and receiving the diagnosis, as well as service managers and policy makers.  This qualitative study will use semi-structured interviews and focus groups involving 10 health care and service providers and 20 members of the public to explore the acceptability of opportunistic identification of undiagnosed or untreated AF during unscheduled EMS ambulance contacts in patients not requiring hospitalisation. Data will be analysed thematically and the findings used to inform the development of new policy and a proposed care pathway for people with AF detected in the community by emergency services.