Influence of diabetes mellitus on the invasive assessment of myocardial ischemia in patients with coronary artery disease

Abstract

Introduction: Current guidelines recommend the physiological evaluation of borderline coronary artery stenoses using hyperemic (FFR) and non-hyperemic (iFR/RFR) methods. However, comorbidities like diabetes mellitus (DM) may influence the results.

Objectives: We sought to investigate the impact of DM and insulin treatment on the discordance between FFR and iFR/RFR. 

Patients and methods: A total of 417 intermediate stenoses in 381 patients underwent FFR and iFR/RFR assessment. FFR ≤0.80 and iFR/RFR ≤0.89 indicated significant ischemia. Patients were categorized based on DM diagnosis and insulin treatment status.

Results: Of the 381 patients, 154 (40.4%) had DM. Among these, 58 patients (37.7%) received insulin treatment. Diabetic patients had higher body mass index and HbA1c levels, and lower ejection fraction. FFR and iFR/RFR analyses were conducted in 417 vessels with available measurements for both tests. A good correlation between FFR and iFR/RFR was confirmed in both diabetic (R = 0.77) and non-diabetic (R = 0.74) patients. Discordance between FFR and iFR/RFR occurred in approximately 20% of cases, and the frequency of discordance was not affected by the diabetic status. However, insulin-treated DM was independently associated with a higher risk of negative FFR and positive iFR/RFR discordance (odds ratio, 4.61; 95%CI, 1.38-15.40; P = 0.01).

Conclusions: FFR and iFR/FFR discordance was common, and insulin-treated DM was associated with an increased risk of negative FFR and positive iFR/RFR discordance.