Understanding for whom, under what conditions, and how atrial fibrillation screening interventions are successful: a realist review

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): European Union’s Horizon 2020 research and innovation programme.

The treatment of atrial fibrillation (AF) with oral anticoagulants reduces stroke risk. Most initial AF diagnoses result from symptom related rhythm monitoring or are after stroke. However, as AF is often asymptomatic detecting it by screening could initiate oral anticoagulant treatment.

We aimed to understand for whom, under what conditions, and how AF screening programmes can increase the number of new AF diagnoses and lead to guideline-adherent care.

A realist review of AF screening for those aged ≥18 years. We developed an initial programme theory; systematically searched four databases until October 2022; and selected documents that included details about factors relating to the implementation of AF screening programmes. We extracted, analysed, and synthesised data using realist techniques to create context–mechanism–outcome configurations, and a refined programme theory.

We screened 2,707 documents and included 70. The refined programme theory included 15 context–mechanism–outcome configurations to explain how different screening programme implementation affects outcomes. Key factors in successful implementation included 1) locations accessible to those at most risk of undiagnosed AF; 2) targeted, inclusive invitations; 3) training to increase understanding and competence of those undertaking screening; 4) using digital technology for convenience and accuracy; 5) organisational support mechanisms such as automated prompts to increase awareness of who to screen; and 6) standardised follow-up pathways. The best system for screening is unclear. Single time point screening is convenient, potentially leading to higher uptake. Prolonged screening may result in a higher paroxysmal AF yield (Figure 1).

Well implemented AF screening programmes could increase the number of new AF diagnoses and lead to guideline-adherent care, thereby reducing stroke risk.