Outcomes of deferred revascularisation following negative fractional flow reserve in diabetic and non-diabetic patients: a meta-analysis

BACKGROUND: Fractional Flow Reserve (FFR) is a widely applied invasive physiological assessment, endorsed by major guidelines to aid in the decision to perform or defer revascularisation. While a threshold of > 0.8 has been applied universally, clinical outcomes may be affected by numerous factors, including the presence of diabetes. This meta-analysis aims to investigate the outcomes of diabetic versus non-diabetic patients in whom revascularisation was deferred based on negative FFR. METHODS: We performed a meta-analysis investigating the outcomes of diabetic and non-diabetic patients in whom revascularisation was deferred based on negative FFR. A search was performed on MEDLINE, PubMed and EMBASE, and peer-reviewed studies that reported MACE for diabetic and non-diabetic patients with deferred revascularisation based on FFR > 0.8 were included. The primary end point was MACE. RESULTS: The meta-analysis included 7 studies in which 4275 patients had revascularisation deferred based on FFR > 0.8 (1250 diabetic). Follow up occurred over a mean of 3.2 years. Diabetes was associated with a higher odds of MACE (OR = 1.66, 95% CI 1.35–2.04, p = < 0.001), unplanned revascularisation (OR = 1.48, 95% CI 1.06–2.06, p = 0.02), all-cause mortality (OR = 1.74, 95% CI 1.20–2.52, p = 0.004) and cardiovascular mortality (OR = 2.08, 95% CI 1.07–4.05, p = 0.03). CONCLUSIONS: For patients with stable coronary syndromes and deferred revascularisation based on FFR > 0.8, the presence of diabetes portends an increased long-term risk of MACE compared to non-diabetic patients. Trail registration URL: https://www.crd.york.ac.uk/PROSPERO/; Unique identifier: CRD42022367312. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12933-023-01751-5.