Computational Fractional Flow Reserve Research Articles

Local Flow Patterns After Implantation of Bioresorbable Vascular Scaffold in Coronary Bifurcations - Novel Findings by Computational Fluid Dynamics.

Development of methods for accurate reconstruction of bioresorbable scaffolds (BRS) and assessing local hemodynamics is crucial for investigation of vascular healing after BRS implantation.Methods and Results:Patients with BRS that crossed over in a coronary bifurcation were included for analysis. Reconstructions of the coronary lumen and BRS were performed by fusion of optical coherence tomography and coronary angiography generating a tree model (TM) and a hybrid model with BRS (TM-BRS). A virtual BRS model with thinner struts was created and all 3 models were analyzed using computational fluid dynamics to derive: (1) time-average shear stress (TASS), (2) TASS gradient (TASSG), which represents SS heterogeneity, and (3) fractional flow reserve (FFR). Reconstruction of the BRS was successful in all 10 patients. TASS and TASSG were both higher by TM-BRS than by TM in main vessels (difference 0.27±4.30 Pa and 10.18±27.28 Pa/mm, P<0.001), with a remarkable difference at side branch ostia (difference 13.51±17.40 Pa and 81.65±105.19 Pa/mm, P<0.001). With thinner struts, TASS was lower on the strut surface but higher at the inter-strut zones, whereas TASSG was lower in both regions (P<0.001 for all). Computational FFR was lower by TM-BRS than by TM for both main vessels and side branches (P<0.001). Neglecting BRS reconstruction leads to significantly lower SS and SS heterogeneity, which is most pronounced at side branch ostia. Thinner struts can marginally reduce SS heterogeneity.

TCT-72 Computational fractional flow reserve derived from three-dimensional intravascular ultrasound: a new algorithm of fusion between anatomy and physiology

Fractional flow reserve (FFR) and intravascular ultrasound (IVUS) imaging, respectively, are considered as the “gold standard” for functional and anatomical assessments of angiographic intermediate stenoses. Associating both in a single method could optimize diagnosis and treatment of coronary

Correction to: Assessing Computational Fractional Flow Reserve From Optical Coherence Tomography in Patients With Intermediate Coronary Stenosis in the Left Anterior Descending Artery.

HomeCirculation: Cardiovascular InterventionsVol. 10, No. 1Correction to: Assessing Computational Fractional Flow Reserve From Optical Coherence Tomography in Patients With Intermediate Coronary Stenosis in the Left Anterior Descending Artery Free AccessCorrectionPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessCorrectionPDF/EPUBCorrection to: Assessing Computational Fractional Flow Reserve From Optical Coherence Tomography in Patients With Intermediate Coronary Stenosis in the Left Anterior Descending Artery Originally published6 Jan 2017https://doi.org/10.1161/HCV.0000000000000022Circulation: Cardiovascular Interventions. 2017;10This article corrects the followingAssessing Computational Fractional Flow Reserve From Optical Coherence Tomography in Patients With Intermediate Coronary Stenosis in the Left Anterior Descending ArteryIn the article by Ha et al, “Assessing Computational Fractional Flow Reserve From Optical Coherence Tomography in Patients With Intermediate Coronary Stenosis in the Left Anterior Descending Artery,” which published online August 8, 2016, and appeared in the August 2016 issue of the journal (Circ Cardiovasc Interv. 2016;9:e003613. DOI: 10.1161/CIRCINTERVENTIONS.116.003613), a correction is needed.On page 4, Figure 2, has been replaced.This correction has been made to the current online version of the article, which is available at http://circinterventions.ahajournals.org/content/9/8/e003613.Download figureDownload PowerPointFigure 2. Correlation and agreement between fractional flow reserve (FFR) and FFROCT. Between FFR and FFROCT, (A) the correlation was good and (B) agreement was acceptable. FFROCT indicates computational FFR by optical coherence tomography (OCT). Previous Back to top Next FiguresReferencesRelatedDetailsCited By Hlaváčová K, Kaňovský J, Kask I, Pospíšil D, Hudec M and Kala P (2022) Coronary physiology assessment: a routine method in a modern catheterization center, Intervenční a akutní kardiologie, 10.36290/kar.2022.036, 21:4, (229-239), Online publication date: 19-Dec-2022. Related articlesAssessing Computational Fractional Flow Reserve From Optical Coherence Tomography in Patients With Intermediate Coronary Stenosis in the Left Anterior Descending ArteryJinyong Ha, et al. Circulation: Cardiovascular Interventions. 2016;9 January 2017Vol 10, Issue 1 Advertisement Article InformationMetrics © 2017 American Heart Association, Inc.https://doi.org/10.1161/HCV.0000000000000022PMID: 28062519 Originally publishedJanuary 6, 2017 PDF download Advertisement

The effect of blood pressure on non-invasive fractional flow reserve derived from coronary computed tomography angiography.

The aim of this study is to assess the effect of blood pressure (BP) on coronary computed tomography angiography (CTA) derived computational fractional flow reserve (CTA-FFR). Twenty-one patients who underwent coronary CTA and invasive FFR were retrospectively identified. Ischemia was defined as invasive FFR ≤0.80. Using a work-in-progress computational fluid dynamics algorithm, CTA-FFR was computed with BP measured before CTA, and simulated BPs of 60/50, 90/60, 110/70, 130/80, 150/90, and 180/100mmHg respectively. Correlation between CTA-FFR and invasive FFR was assessed using Pearson test. The repeated measuring test was used for multiple comparisons of CTA-FFR values by simulated BP inputs. Twenty-nine vessels (14 with invasive FFR ≤0.80) were assessed. The average CTA-FFR for measured BP (134 ± 20/73 ± 12mmHg) was 0.77 ± 0.12. Correlation between CTA-FFR by measured BP and invasive FFR was good (r = 0.735, P < 0.001). For simulated BPs of 60/50, 90/60, 110/70, 130/80, 150/90, and 180/100mmHg, the CTA-FFR increased: 0.69 ± 0.13, 0.73 ± 0.12, 0.75 ± 0.12, 0.77 ± 0.11, 0.79 ± 0.11, and 0.81 ± 0.10 respectively (P < 0.05). Measurement of the BP just before CTA is preferred for accurate CTA-FFR simulation. BP variations in the common range slightly affect CTA-FFR. However, inaccurate BP assumptions differing from the patient-specific BP could cause misinterpretation of borderline significant lesions. • The blood pressure (BP) affects the CTA-FFR computation. • Measured BP before CT examination is preferable for accurate CTA-FFR simulation. • Inaccurate BP assumptions can cause misinterpretation of borderline significant lesions.

Assessing Computational Fractional Flow Reserve From Optical Coherence Tomography in Patients With Intermediate Coronary Stenosis in the Left Anterior Descending Artery.

Intravascular optical coherence tomography (OCT) imaging provides limited information on the functional assessment of coronary stenosis. We evaluated a new approach to OCT image-based computation modeling, which can be used to estimate the fractional flow reserve (FFR) in patients with intermediate coronary stenosis. Ninety-two patients with intermediate diameter stenosis in the left anterior descending artery underwent both FFR measurement with pressure wires and OCT examination. Using the OCT data, a computational fluid dynamics algorithm was used to calculate the computational FFR (FFROCT). The diagnostic performance of the FFROCT was assessed based on the pressure wire-based FFR. The median FFR and FFROCT values were 0.86 (0.79-0.89) and 0.89 (0.82-0.94), respectively. The average diameter stenosis in quantitative coronary angiography and area stenosis in OCT were 58.1±13.4% and 67.5±13.5%, respectively. The FFROCT was better correlated to the FFR than were the anatomic variables (r=0.72; P<0.001 versus r=0.46; P<0.001 for minimal luminal diameter on quantitative coronary angiography or r=0.57; P<0.001 for minimal lumen area on OCT). When functionally significant stenosis was defined as an FFR cutoff value of ≤0.8, FFROCT resulted in 88.0% accuracy, 68.7% sensitivity, and 95.6% specificity. The positive and negative predictive values were 84.2% and 89.0%, respectively. The computation of FFROCT enables assessment not only of anatomic information, but also of the functional significance of intermediate stenosis. This measurement may be a useful approach for the simultaneous evaluation of the functional and anatomic severity of coronary stenosis.

Coronary CT angiography derived morphological and functional quantitative plaque markers correlated with invasive fractional flow reserve for detecting hemodynamically significant stenosis

ObjectiveCompare morphological and functional coronary plaque markers derived from coronary CT angiography (CCTA) for their ability to detect lesion-specific ischemia. Materials and methodsData of patients who had undergone both dual-source CCTA and invasive fractional flow reserve (FFR) measurement within 3 months were retrospectively analyzed. Various quantitative stenosis markers were derived from CCTA: Corrected coronary opacification (CCO), transluminal attenuation gradient (TAG), remodeling index (RI), computational FFR (cFFR), lesion length (LL), vessel volume (VV), total plaque volume (TPV), and calcified and non-calcified plaque volume (CPV and NCPV). Discriminatory power of these markers for flow-limiting versus non-significant coronary stenosis was assessed against invasive FFR as the reference standard. ResultsThe cohort included 37 patients (61 ± 12 years, 68% male). Among 37 lesions, 11 were hemodynamically significant by FFR. On a per-lesion level, sensitivity and specificity of TPV, CPV, and NCPV for hemodynamically significant stenosis detection were 88% and 74%, 67% and 53%, and 92% and 81%, respectively. For CCO, TAG, RI, and cFFR these were 64% and 86%, 35% and 56%, 82% and 54%, and 100% and 90%, respectively. At ROC analysis, only TPV (0.78, p = 0.013), NCPV (0.79, p = 0.009), cFFR (0.85, p = 0.003), and CCO (0.82, p = 0.0003) showed discriminatory power for detecting hemodynamically significant stenosis. ConclusionTPV, NCPV, CCO, and cFFR derived from CCTA can aid detecting hemodynamically significant coronary lesions with cFFR showing the greatest discriminatory ability.