Optical coherence tomography‐defined plaque vulnerability in relation to functional stenosis severity stratified by fractional flow reserve and quantitative flow ratio

Abstract

Objectives We sought to investigate that the quantitative flow ratio (QFR) might be associated with optical coherence tomography (OCT)‐defined plaque vulnerability. Background Both functional stenosis severity and plaque instability are related to adverse clinical outcomes in patients with coronary artery disease. Recent studies have shown an association between physiological stenosis severity and the presence of thin‐cap fibroatheroma (TCFA). Measurement of QFR is a novel method for rapid computational estimation of fractional flow reserve (FFR). Methods We investigated 327 de novo intermediate‐to‐severe coronary lesions in 295 stable patients who underwent OCT, FFR, and QFR computation. The lesions were divided into tertiles based on either the FFR or QFR. The OCT findings were compared among these tertiles of FFR and QFR. Each tertile was defined as follows: FFR‐T1 (FFR < 0.72), FFR‐T2 (0.72 ≤ FFR ≤ 0.79), and FFR‐T3 (FFR > 0.79) and QFR‐T1 (QFR < 0.73), QFR‐T2 (0.73 ≤ QFR ≤ 0.78), and QFR‐T3 (QFR > 0.78). Results The prevalence of OCT‐defined TCFA showed graded differences in proportion to the QFR tertiles (25.0% vs. 12.8% vs. 6.6%, p = .003). An overall significant difference in the prevalence of TCFA was found among FFR tertiles (p = .048), although pairwise comparison did not show statistical significance. Compared with FFR‐based classifications, the model that integrated the FFR and QFR categorization improved the incremental reclassification efficacy (relative integrated discrimination improvement, 0.069; p = .002; continuous net reclassification improvement, 0.356; p = .022) for predicting the presence of TCFA. Conclusions OCT‐defined plaque instability was associated with the QFR in angiographically intermediate‐to‐severe lesions. Compared with the FFR alone, the QFR can provide incremental efficacy in predicting the presence of TCFA.

The Association Between Quantitative Flow Ratio and Intravascular Imaging-defined Vulnerable Plaque Characteristics in Patients With Stable Angina and Non-ST-segment Elevation Acute Coronary Syndrome

“…However, the majority of the included lesions (89%) were from patients with stable coronary artery disease and this association needs to be verified in a broader spectrum of patients. Additionally, discrepant results were reported in previous studies examining whether plaque characteristics assessed by OCT ( 14 – 16 ) or VH-IVUS ( 17 – 20 ) had an impact on coronary hemodynamics. Hence, the association between coronary physiology and OCT/IVUS-defined plaque vulnerability remains elusive and warrants more evidence.…”

“…A recent study indicated the link between QFR and the presence of OCT-TCFA in 327 de novo intermediate-to-severe coronary lesions but the majority of these lesions were from stable patients ( 14 ). Here, we further confirmed this relationship in an NSTE-ACS-dominated population and suggested the applicability of QFR in these patients.…”

“…Emerging evidence has established the association between high-risk plaque features and the presence of adverse coronary events ( 11 , 13 ). Recently, QFR was recognized to be associated with the presence of OCT-TCFA in stable patients, and non-culprit lesions in patients with acute coronary syndrome (ACS) ( 14 ). However, the majority of the included lesions (89%) were from patients with stable coronary artery disease and this association needs to be verified in a broader spectrum of patients.…”

Quantitative Flow Ratio Is Related to Intraluminal Coronary Stenosis Parameters as Assessed with Optical Coherence Tomography

“…A recent study by Kanno et al [ 25 ] showed that a lower QFR may be associated to a higher rate of thin capped fibroatheromas in the investigated lesions. We aimed to extend the current knowledge by further assessing plaque vulnerability, as determined by OCT, in dependence of QFR.…”

Lesion Geometry as Assessed by Optical Coherence Tomography Is Related to Myocardial Ischemia as Determined by Cardiac Magnetic Resonance Imaging

“…Besides, CMR can also evaluate the extent of ischemia, which yields a relevant value in risk stratification [ 1 , 8 ]. The correlation between the presence of ischemia and geometry of a coronary lesion has already been shown [ 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 ]; however, to date, no study evaluated whether stenosis parameters predict also the extent of this ischemia. This may be clinically relevant, especially if there is no previous quantification of the ischemic burden because it may give interventionalists insights into the extent of ischemia based on the geometric features of the coronary lesion and may be a valuable addition to functional testings such as FFR or iFR.…”