Favorable impact of FFRCT on myocardial revascularization outcomes: results from an observational real-world registry
Authors: Motoc A , Lammens J , De Potter T , Tanaka K , Belsack D , Vandeloo B , Lochy S , Michiels V , Tsugu T , Van Dalem A , Thorrez Y , Magne J , De Mey J , Cosyns B , Argacha J F 
Published: October 2024

Abstract

Background
Based on excellent clinical outcomes data, coronary computed tomography angiography (CCTA)-derived fractional flow reserve (FFRCT) is endorsed by guidelines to diagnose obstructive coronary artery disease (OCAD)(1). Dedicated outcome analyses in revascularized patients are essential to assess the additional value of FFRCT in revascularization.

Purpose
To assess the impact of FFRCT use on the postprocedural myocardial injury (PMI) and long-term outcomes of patients with OCAD undergoing myocardial revascularization.

Methods
Patients with suspected OCAD on CCTA (at least one stenosis of &gt;50% in any vessel) were included from a 2013-2021 tertiary hospital registry. Propensity score adjusted Cox- regression and logistic regression analysis were used to assess the impact of FFRCT on the outcomes of OCAD patients post-revascularization. PMI was defined as cardiac troponin (cTn)&gt;5 times the 99th percentile URL for percutaneous coronary intervention (PCI) and cTn&gt;10 times the 99th percentile URL for coronary artery bypass graft (CABG) (2). Major adverse cardiovascular events (MACE) comprised all – cause mortality, acute myocardial infarction (AMI), stroke, hospitalization for heart failure (HHF) and new revascularization.

Results
From a registry of 7541 patients, suspected CCTA - derived OCAD was reported in 1601 cases. 559 OCAD patients were revascularized: 386(69.05%) by PCI, 166(29.7%) by CABG and 7(1.25%) by PCI and CABG. FFRCT was performed in 252(45.1%) patients. During a follow-up of 4.4±2.2 years, MACE occurred in 137(24.5%) patients: 43(7.7%) died, 21(3.8%) patients were hospitalized for AMI, 14(2.5%) patients had a stroke, 12 (2.1%) patients had HHF and 77(13.8%) patients had a new revascularization. Survival analysis indicated significant differences in MACE and all-cause mortality–rates between FFRCT use and no FFRCT use (log- rank p = 0.033 and 0.004, Fig 1). Multivariable propensity–adjusted Cox–regression analysis showed a non–significant trend towards reduced MACE risk by using FFRCT (HR 0.736, 95% CI 0.513-1.055, P=0.095) and a significant reduction in all-cause mortality risk (HR 0.476, 95% CI 0.230–0.985, P=0.046). Sub-analysis in the PCI and CABG groups showed no significant association between FFRCT and MACE. Among the 477 patients with available cTn values, 203 (42.5%) had PMI. In the CABG group, FFRCT use correlated with low PMI incidence (5.3% vs. 15.6%, p=0.044). However, multivariable Cox regression analysis revealed no significant association between FFRCT use and PMI(Fig 2).

Conclusion
This observational designed study reveals for the first time that FFRCT reduces post-myocardial revascularization MACE, primarily driven by reduced all-cause mortality. No clear reduction of PMI was observed suggesting that FFRCT value extends beyond procedural enhancements. Although derived from a large real-world registry, these promising observations need to be confirmed by randomized studies.Figure 1Figure 2