Prognostic impact of diabetes mellitus and index of microcirculatory resistance in patients undergoing fractional flow reserve-guided revascularization.
BACKGROUND
The prognostic impact of diabetes mellitus (DM) with or without coronary microvascular dysfunction (CMD) in patients undergoing fractional flow reserve (FFR)-guided revascularization has not been clarified. We sought to investigate the clinical outcomes of patients undergoing FFR-guided revascularization according to the existence of DM and CMD.


METHODS
A total of 283 patients with available FFR data as well as index of microcirculatory resistance (IMR) were selected from the 3 V FFR-FRIENDS study. CMD was defined as an IMR ≥25U. Patients were grouped according to the presence of DM and CMD into group A (DM-, CMD-), group B (DM-, CMD+), group C (DM+, CMD-), and group D (DM+, CMD+). The primary outcome was a major adverse cardiac event (MACE, a composite of myocardial infarction, ischemia-driven revascularization, and cardiac death) at 2 years.


RESULTS
DM patients displayed a notably higher risk of MACEs in comparison with non-DM patients (HR 4.88, 95% CI 1.54-15.48, p = 0.003). MACEs at 2 years among the four groups were 2.2%, 2.0%, 7.0%, and 18.5%, respectively. Group D exhibited a significantly higher risk of MACEs as compared to group A (HR 8.98, 95% CI 2.15-37.41, p = 0.003). Multivariable regression analysis showed that the presence of DM and CMD was an independent predictor of a 2-year MACE (HR 11.24, 95% CI 2.53-49.88, p = 0.002), and integrating CMD into a model with DM increased discriminant ability (C-index 0.683 vs. 0.710, p = 0.010, integrated discrimination improvement 0.015, p = 0.040).


CONCLUSION
Among the patients undergoing FFR-guided revascularization, those with DM and CMD were correlated with an augmented risk of MACEs. Integration of CMD improved risk stratification in predicting the occurrence of a MACE.
['Hu|Xinyang|X|', 'Zhang|Jinlong|J|', 'Lee|Joo Myung|JM|', 'Chen|Zexin|Z|', 'Hwang|Doyeon|D|', 'Park|Jonghanne|J|', 'Shin|Eun-Seok|ES|', 'Nam|Chang-Wook|CW|', 'Doh|Joon-Hyung|JH|', 'Chen|Shaoliang|S|', 'Yang|Junqing|J|', 'Tanaka|Nobuhiro|N|', 'Kuramitsu|Shoichi|S|', 'Matsuo|Hitoshi|H|', 'Takashima|Hiroaki|H|', 'Akasaka|Takashi|T|', 'Koo|Bon-Kwon|BK|', 'Wang|Jianan|J|']
Diabetes mellitus Index of microcirculatory resistance Fractional flow reserve Coronary artery disease Microvascular function