Caristo Diagnostics is a University of Oxford spinout founded in 2018 by cardiologists at the university following a decade of research into coronary inflammation. Its flagship product, CaRi-Heart, is an AI-assisted software platform that extracts measures of coronary inflammation, using the Fat Attenuation Index, from routine cardiac CT angiography scans, and combines these with standard clinical risk factors and plaque presence to estimate long-term cardiovascular mortality risk. A companion product, CaRi-Plaque, provides AI-based coronary plaque analysis and received FDA 510(k) clearance in March 2025. In July 2026 the FDA granted De Novo authorization for CaRi-Heart, making it the first technology authorized in the United States to quantify coronary inflammation from routine CCTA scans. The product received CE mark under the EU MDR process in February 2021 and is commercially available in Europe, the UK and Australia.

Caristo's customers include the NHS, HCA UK, Cleveland Clinic UK, Mayo Clinic UK, Cromwell Hospital and NCH in the United States, along with clinics and cardiology groups in the UK, EU and Australia. The company was selected by NewAmsterdam as worldwide imaging core lab for the REMBRANDT trial and by Abcentra for the Phase 2b FORTIFY trial, where FAI-Score is the primary outcome measure. In January 2026 Aetna announced nationwide coverage for CaRi-Plaque, and the American Medical Association assigned CPT codes 0992T and 0993T for CaRi-Heart analysis, included in the 2026 CPT Codebook. Caristo was also selected by the World Economic Forum as a 2026 Technology Pioneer and was a winner of the 2024 Digital Health Awards and the 2024 Fierce Healthcare Innovation Awards.

The company raised a Series A totalling £13M (US$16.3M) in April 2023, led by Oxford Science Enterprises with participation from BGF, Longwall Venture Partners, Oxford Investment Consultants and the University of Oxford. Frank Cheng was appointed CEO at that time, and Steve Deitsch is listed as CEO on the company's current team page. In 2026 the company expanded its executive team with David Vort as Chief Commercial Officer and Chris Louk as Chief Financial Officer, and it operates offices in Oxford and Stamford, Connecticut.