Diagnostic accuracy of angiography‐based vessel fractional flow reserve after chronic coronary total occlusion recanalization

BACKGROUND: Angiography‐based vessel fractional flow reserve (vFFR) demonstrated a strong correlation with invasive fractional flow reserve (FFR) in both a pre‐ and post‐percutaneous coronary intervention (PCI) setting. However, the role of vFFR and its correlation with post‐PCI FFR in chronic coronary occlusions (CTO) has not been evaluated yet. We sought to investigate the diagnostic performance of post‐PCI vFFR with post‐PCI FFR as a reference in patients undergoing successful CTO PCI. METHODS: Between March 2016 and April 2020, a total of 80 patients from the FFR‐SEARCH (prospective registry) and FFR REACT (randomized controlled trial) studies underwent successful CTO recanalization with post‐PCI FFR measurements. RESULTS: A total of 50 patients (median age 66 (interquartile range [IQR]: 56−74) years, 76% were male) were eligible for the analysis. Median post‐PCI FFR was 0.89 (IQR: 0.84−0.94), while median post‐PCI vFFR was 0.91 (IQR: 0.85−0.94) (p 0.10). Suboptimal physiological results, defined as FFR and vFFR <0.90, were identified in 26 (52%) and in 21 (42%) patients, respectively. A strong correlation (r = 0.82) was found between vFFR and FFR with a mean bias of 0.013 ± 0.051. Receiver‐operating characteristics curve analysis revealed an excellent accuracy of vFFR in predicting FFR <0.90 (area under the curve: 0.97; 95% confidence interval: 0.93−1.00). CONCLUSION: Post‐PCI vFFR shows a good correlation with post‐PCI FFR and a high diagnostic accuracy for post‐PCI FFR ≤0.90 in patients undergoing successful PCI of a CTO lesion.