Impact of Renal Dysfunction on FFR- or IVUS-Guided PCI for Intermediate Coronary Stenosis

A previous FLAVOUR (Fractional Flow Reserve or Intravascular Ultrasonography to Guide PCI) trial reported that percutaneous coronary intervention (PCI) guided by fractional flow reserve (FFR) was noninferior to intravascular ultrasound (IVUS)-guided strategies in terms of the composite outcome of death, myocardial infarction, or revascularization at 24 months (patient-oriented composite outcome [POCO]).

This post hoc secondary analysis of the FLAVOUR trial evaluated the impact of renal dysfunction on lesion characteristics, treatment patterns, and clinical outcomes according to FFR- or IVUS-guided strategies in patients with intermediate coronary stenosis.

Patients were classified according to renal function as chronic kidney disease (CKD) or non-CKD. The primary endpoint was POCO.

Among 1,617 patients, 101 (6.2%) had CKD. Compared with non-CKD patients, CKD patients had greater anatomic disease burden on IVUS but similar pre-PCI FFR. CKD patients underwent PCI more frequently (60.4% vs 46.9%; P = 0.009), mainly in the IVUS-guided group, and had a higher POCO rate (17.8% vs 7.8%; P = 0.001). These differences were more evident in PCI-treated patients, whereas deferred lesions showed broadly similar outcomes. No statistically significant differences in outcomes were detected between FFR- and IVUS-guided strategies within renal function strata. Formal interaction analyses showed no significant effect modification by renal function for POCO or any individual endpoint (all P for interaction >0.05).

CKD was associated with higher PCI and POCO rates, whereas no significant renal function-by-strategy interaction was detected. These exploratory findings require prospective validation. (Fractional Flow Reserve and Intravascular Ultrasound for Clinical Outcomes in Patients with Intermediate Stenosis; NCT02673424).