Anatomical and Functional Discrepancy in Diabetic Patients With Intermediate Coronary Lesions - An Intravascular Ultrasound and Quantitative Flow Ratio Study

Background: Data regarding the performance of computational fractional flow reserve in patients with diabetes mellitus (DM) remain scarce. This study sought to explore the impact of DM on quantitative flow ratio (QFR) and its association with intravascular ultrasound (IVUS)-derived anatomical references.

Methods and results: IVUS and QFR were retrospectively analyzed in 237 non-diabetic and 93 diabetic patients with 250 and 102 intermediate lesions, respectively. Diabetics were further categorized based on adequate (HbA1c <7.0%: 47 patients with 53 lesions) or poor (HbA1c ≥7.0%: 46 patients with 49 lesions) glycemic control. Lesions with QFR ≤0.8 or minimum lumen area (MLA) ≤4.0 mm²and plaque burden (PB, %) ≥70 were considered functionally or anatomically significant, respectively. PB increased, and MLA decreased stepwise across non-diabetics, diabetics with adequate glycemic control and those with poor glycemic control. In contrast, QFR was similar among the 3 groups. PB correlated significantly with the QFR for lesions in non-diabetics, but not for lesions in diabetics. DM was independently correlated with the functionally non-significant lesions (QFR >0.8) with high-risk IVUS features (MLA ≤4.0 mm²and PB ≥70; OR 2.053, 95% CI: 1.137-3.707, P=0.017). When considering the effect of glycemic control, HbA1c was an independent predictor of anatomical-functional discordance (OR 1.347, 95% CI: 1.089-1.667, P=0.006).

Conclusions: Anatomical-functional discordance of intermediate coronary lesions assessed by IVUS and QFR is exacerbated in patients with diabetes, especially when glycemia is poorly controlled.