Shared learning database

Eastern AHSN & Cambridge University Hospitals NHS Foundation Trust
Published date:
November 2019

In October 2017, Cambridge University Hospitals Foundation Trust (CUH) worked with Eastern Academic Health Science Network (AHSN) to establish a patient-centred multidisciplinary stroke prevention service.

The service is called Screening and Optimising Stroke Prevention in Atrial Fibrillation (SOS-AF). All people admitted to medical wards at the hospital routinely have a 12-lead ECG, which the team accesses through electronic patient records. The team screen all medical admissions, to ensure that those previously undiagnosed with AF are not missed.

For all new and old AF patients, the team assess stroke risk using the CHA2DS2-VASc assessment tool and consider the risks and benefits of anticoagulation. Where appropriate, treatment is started before people return home from hospital. In the first 12 months, the team reviewed nearly 15,000 people, diagnosed more than 400 people with AF and improved access to effective stroke prevention treatment preventing at least 16 strokes and 8 deaths.

Does the example relate to a general implementation of all NICE guidance?
Does the example relate to a specific implementation of a specific piece of NICE guidance?


Aims and objectives

Atrial fibrillation (AF) is the most common heart rhythm condition that causes an irregular and often abnormally fast heart rate. People with AF are more at risk of having a stroke. Evidence-based treatment to prevent stroke for people with AF is available. However, many people with AF go undetected and therefore do not receive effective medicines and treatment that can prevent stroke. The Screening and Optimising Stroke Prevention in Atrial Fibrillation (SOS-AF) project established a stroke prevention service based in Cambridge University Hospital in 2017. This specialist service consists of 2 stroke consultants, 1 registrar and 2 specialist nurses.

The service aims and objectives are to provide:

• Active screening for AF among all patients admitted to medical wards to identify undiagnosed AF, as well as reviewing stroke prevention measures and offering support for those with known AF.

• To assess stroke risk and bleeding risk and initiate anticoagulation where appropriate

• Deliver patient education and support, enabling informed decision making and improve patient experience

• Specialist assessment and advice to primary and secondary care

• Increasing AF awareness within patient groups and community All the aims and objectives of the project align with the recommendations stated in the NICE guidelines for AF management. Moreover, priority areas for improvement of care for people with AF are highlighted in the NICE Quality Standard for AF (QS93).

Our service meets three of the QS93 quality statements by ensuring that adults with non-valvular AF and a CHA2DS2-VASc stroke risk score of 2 or above are offered anticoagulation and are not prescribed aspirin as monotherapy for stroke prevention. All our patients are given the opportunity to discuss the choice of suitable anticoagulants in a timely manner and receive treatment from a specialist team. A film about the service can be found at

Reasons for implementing your project

AF causes at least 25% of all ischaemic strokes, and this cardioembolic subtype is often more severe compared to other stroke aetiologies, constituting a two-fold increase in median total healthcare costs due to their greater burden of disability, dementia and death.

As highlighted in NICE guidelines, anticoagulation is the only effective treatment for stroke prevention in AF. Appropriate management of at-risk individuals could prevent 4500 strokes and 3000 deaths each year in the United Kingdom. However, due to the perceived risk of complications from anticoagulation, for example, unwanted gastrointestinal and intracerebral bleeding, low rates of anticoagulation use are seen, especially among older patients where up to half do not receive anticoagulation. Sentinel Stroke Audit (SSNAP) data highlights that 47% of U.K. AF patients were not anticoagulated at the time of their stroke in 2017.

The burden of AF is growing rapidly within the population of medical patients admitted acutely to secondary care. This was the most important finding of the research carried out by the Department of Stroke Medicine at Cambridge University Hospital in 2014-15 which highlighted the following:

1). 15% of acute medical admissions had AF in 2015, contrasting previous estimates of AF burden on acute hospital admissions (around 3-6%).

2). These patients are older with multiple comorbidities, and a high stroke-risk (median CHA2DS2-VASc score=4.4).

3). On average, 1 new AF case was diagnosed every day. In addition, suboptimal anticoagulation rates in the community and in secondary care emphasised the need for an in-hospital stroke prevention team providing specialist anticoagulation advice to medical inpatient teams as well as local general practitioners.

Over the 12 months of the project, our data has showed that the prevalence of AF increased further to 22.1% and now more than one in five people admitted to medical wards at the hospital have AF.

How did you implement the project

The project team formed an AF oversight-group (Stroke Consultant, GP Lead from the CCG, representatives from cardiology and haematology) and alongside feedback from GPs and patients, we developed the SOS-AF service.

The service systematically screens all people admitted to acute medical wards for AF using electronic notes and admission 12-lead ECG results. We holistically risk-assess an individual’s suitability for anticoagulation and coordinate with medical teams and patients to ensure those appropriate receive anticoagulation without delay. Furthermore, the service accepts referrals from primary and secondary care, seen either in a weekly outpatient clinic or discussed at a multidisciplinary meeting.

The development of SOS-AF was based around a commitment to increasing patient health awareness and supporting self-management. Two dedicated Clinical Nurses with specialist knowledge of cardiology and stroke prevention were essential for successful implementation of the pathway. This allowed large numbers of patients to be screened for AF and more individuals to receive anticoagulation reducing their risk of debilitating stroke.

We established a database, updated daily, to allow continuous audit and evaluation of our service. Results are reviewed monthly by the team to ensure the service meets the needs of a dynamic healthcare environment.


Key findings

In the first year of running the service, we have:

• Screened 14979 general medical patients, identifying 402 new cases of AF.

• Advised medical team/GPs on 628 occasions with regards to consideration of starting/restarting anticoagulation or changing to appropriate dose.

• Advised not to anticoagulate 158 patients, where the adverse risks outweighed the benefits, with clear documentation to guide both healthcare professionals and patients.

• 401 patients were started on anticoagulation directly as a result of our input, equating to prevention of 16 AF-related stroke and 8 deaths (Number needed- to treat (NNT) with anticoagulation to prevent one AF-stroke is 25).

• Calculations using the median length of stay of a cardioembolic stroke in the Trust (15.9 days) equates to reducing 254 bed days annually, a saving to the Trust of £89,000.

• Direct savings to the NHS and wider social care costs from our service are even greater, approximately £350,000 in the first-year post-stroke (based on preventing 16 strokes at £13,340 direct NHS costs and £8,503 additional social care costs per patient/1-year (SSNAP data)). These figures do not consider savings on long-term effects of large AF-related strokes in terms of loss of income and the effects on families.

• In 2016 only 55.7% of patients with established AF were admitted on anticoagulation to CUH. This figure has improved to 65.1%, highlighting the importance of specialist input in AF-stroke prevention.

“We have shown that it is possible to screen a very large number of people for AF in hospital using electronic records and ECG tests that are already being performed as part of routine care within the NHS. This proactive approach to AF detection ensures that we are making every contact count to improve patients access to timely stroke prevention. Patient feedback and outcomes have been fantastic.

The cost savings from the potential strokes that are prevented far outweigh the costs of providing the service. We sometimes overlook hospitals as a key setting for preventive medicine, and the SOS-AF results show how efficiently and effectively a population approach to stroke prevention can be implemented at scale in this setting. Furthermore, the service is having far-reaching impacts in both secondary and primary care. We have been sharing this service model widely with others and would be delighted if more hospitals adopt this innovative approach.” – Dr Amanda Buttery, Senior Programme Manager Eastern AHSN.

Key learning points

  • All people admitted to the medical wards in the hospital routinely have a 12-lead ECG which is available on the electronic health record system. This enables the team to efficiently review all people admitted to medical wards in real-time at no extra diagnostic cost for an ECG.
  • Medical inpatients have multiple comorbidities conveying a high risk of stroke. One in five (22.1%) people admitted to medical wards have AF. Screening in secondary care and optimising anticoagulation where multidisciplinary expertise is available is an efficient approach to improving AF detection and management. Our Clinical Nurse Specialists with expertise in cardiology and stroke prevention underpin the service model and help building trusting relationships with colleagues in primary care and General Practitioners through education sessions.
  • A small and dedicated secondary care multidisciplinary team focused on improving AF diagnosis and treatment can have large impacts on regional population health. The financial savings vastly outweigh the cost of service delivery, which is around £90,000 for staff salaries per year, while saving at least £350,000 per year in the number of potential strokes avoided.

Contact details

Simon Day & Dr Kayvan Khadjooi
Senior Content Manager & Consultant in Stroke Medicine
Eastern AHSN & Cambridge University Hospitals NHS Foundation Trust
Email: &

Secondary care
Is the example industry-sponsored in any way?

Funding for this project was initially provided through the Network of AHSN’s partnership with the BMS-Pfizer Alliance for Stroke Prevention in AF Competitive Grant Scheme