Sensyne Health plc analysed anonymised, routinely collected data from nearly half a million NHS patients as part of a study seeking to identify if there are benefits to the use of blood thinning agents (anticoagulants) for all heart failure patients. Heart failure is a highly heterogeneous disease which affects more than one million UK adults, is one of the most common causes of hospital admission and is responsible for 10,000 deaths a year. It severely compromises a patient's quality of life, and treating it comes with significant costs, amounting to 1-2% of the NHS' annual budget (c. £625 million). Heart failure is associated with the development of blood clots which can break away and block blood vessels in the brain, causing strokes. NICE guidelines have recommended anticoagulants for heart failure patients who have an irregular heartbeat, which increases the likelihood of blood clots forming. However, this treatment is also associated with increased bleeding risks in the stomach and brain. Currently, two different classes of anticoagulant are commonly used. Warfarin, an off-patent drug developed in the 1940s, and a newer group of medicines known as NOACs developed over the last decade. Sensyne compared the anonymised data over three years of heart failure patients with no record of anti-coagulant prescription (the 'control arm') with that of patients prescribed either warfarin or NOACs. The benefit of anticoagulants in patients with an irregular heartbeat is well documented. The data in this study also suggested a small but statistically significant survival benefit for heart failure patients without an irregular heart on anticoagulants, but further analysis is required to confirm if the difference is clinically relevant, and if so which subgroups of patients would benefit the most. The analysis also suggests that there may be relevant differences, not only between the use of warfarin compared to NOACs, but also between the NOACs currently in use. This is an early observation worthy of further exploration. The expense and complexity of randomised controlled trials means that they tend to be focused on highly defined, specific groups of patients which do not necessarily reflect the diversity observed in day to day practice. By contrast, Sensyne's in silico analysis of the real-world data in electronic patient records, offers the enticing potential of a faster, more representative and cost-effective alternative. These findings are interesting in their own right, but the combination of these standard, statistical approaches with the application of Sensyne Health's machine learning patient stratification algorithm that identifies different subgroups of heart failure patients is where the opportunities lie for enhanced analysis, insights and clinical understanding. Sensyne Health, a leading company in this field, has developed a unique partnership relationship with NHS Trusts to enable it to analyse ethically sourced, anonymised patient data to undertake such research.