Among patients with complex coronary artery disease (CAD) undergoing multivessel percutaneous coronary intervention (PCI) with fractional flow reserve (FFR) guidance, low post-PCI FFR was associated with a significantly higher rate of target vessel failure (TVF) on both the vessel and patient levels, new study results show.
Yuhei Kobayashi, from New York Presbyterian Brooklyn Methodist Hospital and Weill Cornell Medical College, New York, presented these results on behalf of the FAME 3 investigators at the Transcatheter Therapeutics (TCT) Conference 2022 in Boston. The results were reported in a manuscript that was simultaneously published online in Circulation: Cardiovascular Interventions.
The recently published FAME 3 trial, was a multicenter, international, randomized study that compared outcomes of multivessel coronary artery disease with FFR-driven PCI vs. CABG. CABG proved to have better outcomes; however, many patients will continue to have multivessel PCI for a number of different reasons.
Currently, FFR is mostly utilized to determine the physiological significance of a lesion prior to intervention, but post -CI FFR may also provide prognostic value, and perhaps indicate the need for further optimization. The prognostic value of measuring post-PCI FFR after DES implantation in patients with complex 3-vessel CAD is unknown. Further, the impact of intravascular imaging (IVUS/OCT) is also poorly defined in this setting
The investigators performed a post hoc analysis of the FAME 3 trial using univariate analysis to measure the relationship of post-PCI FFR to a primary outcome of TVF, defined as a composite of cardiac death, target vessel myocardial infarction (TVMI) and target vessel revascularization (TVR) at 1 year. Chronic and acute coronary syndromes were included, but recent ST-elevation myocardial infarction, cardiogenic shock and severe left ventricular function were excluded. A vessel-level (lowest target vessel FFR) and patient-level (lowest post-FFR value in any vessel) analysis was performed.
Among 757 patients randomized to PCI, 461 (61%) had post-PCI FFR. The PCI patients’ mean age was 65 years old, more than 80% were male, and more than 90% were white. On a vessel level, a univariate analysis demonstrated post-PCI FFR to be a significant predictor of TVF (hazard ratio [HR] 0.67, 95% confidence interval [CI] 0.48-0.93, for each 0.1-unit increase; p=0.0165). On a patient level, the single lowest post-PCI FFR value was also found to be a significant predictor of TVF (HR 0.65, 95% CI 0.48-0.89, for each 0.1-unit increase; p=0.0074). In multivariate analysis, post-PCI FFR was an independent predictor of TVF. Notably, intravascular imaging guidance did not have an impact on the primary outcome, although imaging was only performed in a small number of patients (11.1%).
When asked whether the study conclusion would have benefited from mandating post PCI FFR in the study rather than using post hoc analysis, William Fearon, MD, of Stanford University, a FAME 3 investigator, replied: “All the previous data had shown the prognostic impact, and I’m still not sure on the patient level data suggest that just identifying one vessel with low FFR has implications. And so it may just be that this is picking up the burden of atherosclerosis, and whether you can correct that by putting in more stents, we will have to wait for DEFINE GPS and other studies looking at that.”
The FAME 3 trial was funded by Medtronic and Abbott Vascular.
Image Credit: Jason Wermers/CRTonline.org