Clinical Outcomes of Deferred Revascularisation Using Fractional Flow Reserve in Diabetic Patients

Background: Fractional flow reserve (FFR) is used to assess the functional significance of coronary artery lesions. Diabetic patients are associated with high burden of atherosclerosis and microvascular dysfunction. We studied the clinical outcomes of diabetic patients who underwent FIR-guided deferred revascularisation. Methods: Consecutive patients from a single large volume centre who underwent FFR assessment were included. Clinical endpoints were prospectively collected using the national electronic care records system. The primary endpoint was defined as the four-year risk of the vessel-oriented composite outcome of cardiac death, vesselrelated myocardial infarction (VMI), and vessel-related urgent revascularisation (VUR). Absolute FFR values groups (0.81 to 0.85: 0.86 to 0.90; and >0.90) were used to further stratify patient outcomes. Results: FIR-guided deferred revascularisation occurred in 860 patients (63%), of whom 159 were diabetic. The primary endpoint was significantly higher in the diabetic compared to the non-diabetic group [HR 1.76 (95%CI 1.08 to 2.88), P = 0.024]. The difference was driven from cardiac death (6.3% vs. 3.0%, P = 0.044) and VMI (5.0% vs. 1.7%, P = 0.012) but not VUR (8.8% vs. 5.1%, P = 0.07). There was a significant decrease in the incidence of the primary endpoint in the diabetic group according to FFR groups (23.6%,12.3%, 2.4%, P = 0.001) with comparable clinical outcomes in the non-diabetic group (11.8%, 6.4%, 7.4%, P = 0.085). Conclusions: Our study demonstrated an increased risk of death and target vessel MI in diabetic patients undergoing FFR-guided deferred revascularisation compared to non-diabetic group. Nonetheless, FFR remained a useful tool to identify those at future risk, mainly in diabetic patients. (C) 2019 Elsevier Inc. All rights reserved.