Impact of Minimal Lumen Area Measured by Intravascular Ultrasound on Revascularization Decision in Grey Zone Fractional Flow Reserve:
Data From IRIS FFR Registry
Joong Min Lee1, Jinho Lee1, Yeonwoo Choi1, Hoyun Kim1, Do-Yoon Kang1, Jung-Min Ahn1, Duk-Woo Park1, Seung-Jung Park1
Asan Medical Center, Korea (Republic of)1
Theoptimal revascularization strategy for coronary stenosis with grey-zonefractional flow reserve (FFR) value (0.75-0.80) is still debated. This studyinvestigated the prognostic impact of the lesion characteristics measured byintravascular ultrasound (IVUS) in grey-zone FFR.
Atotal of 734 native coronary stenoses with grey-zone FFR in 734 patients fromthe prospective multicenter IRIS-FFR registry were simultaneously evaluated byIVUS. The primary outcome was a composite of cardiac death, myocardialinfarction (MI) and target vessel revascularization.
Among the 734 patients,revascularization was deferred for 293 patients and performed for 441. During amedian follow-up of 4.4 years, the primary outcome occurred in 31 (10.58%)patients in deferred group and 42 (9.52%) in revascularization group. Minimallumen area (MLA) measured by IVUS was an important factor of the primaryoutcome in deferred group, with the best cut-off value of 2.62 mm2
(area under curve 0.639). The incidence rate of the primary outcome wassignificantly higher in deferred group than revascularization group if the MLAwas smaller than 2.62 mm2
(17.4% vs. 10.9%, adjusted hazard ratio[HR] 0.546, 95% confidence interval [CI] 0.31-0.96, P=0.036). However, if MLAwas equal or larger than 2.62 mm2
, the primary outcome was notdifferent between deferred and revascularization group (6.5% vs. 13.6%,adjusted HR 1.788, 95% CI 0.75-4.26, P=0.190).
Forcoronary stenoses with grey-zone FFR and smaller MLA measured by IVUS,revascularization was associated with better clinical outcomes. In addition,high plaque burden measured by IVUS also had clinical implication for the needfor revascularization. The incorporation of FFR and IVUS may improve therevascularization decision in native coronary stenoses with grey-zone FFR.