The ramus artery contributes to the development of turbulence, which may influence computed tomography (CT) derived fractional flow reserve (FFRCT) even without coronary artery disease (CAD). The relationship between ramus‐induced turbulence and FFRCT is unclear.

Impact of ramus coronary artery on computed tomography derived fractional flow reserve (FFRCT) in no apparent coronary artery disease

Diagnostic technology based on magnetic fields is commonly used in medicine for diagnosis and therapy. However, the exposure to strong electromagnetic fields has adverse outcomes in patients. Thus, the objective of the current study is to investigate the effect of applying external uniform magnetic fields on the blood flow in both healthy and diseased cases of right coronary artery and determine the safe values of the applied magnetic field strengths. The diseased cases include a 40% stenosed artery along with two blood disorder cases with a hematocrit level of 20% and 60%. A comprehensive three-dimensional steady non-Newtonian flow model is developed using the Casson model to investigate the effect of the magnetic field on both shear rate and hematocrits. The model is numerically simulated at different values of magnetic field strengths and its orientation. The results indicated that the magnetic field in the Y-direction has a dominant effect compared to other directions. Moreover, the maximum increase in the main branch mass flow rate fraction is about 6.2%. Another interesting finding is that the wall shear stress is slightly affected by the magnetic field strength. For the stenosed case, it is found that the high magnetic field strengths can reduce the formulation of the vortices and hence reduce the risk of thrombosis, which agrees with published works. Additionally, the obtained results confirm that using a magnetic field up to 11.7 T, which is used in magnetic resonance imaging devices, is safe, and has a slight effect on blood flow parameters such as the wall shear stress.

Effect of external magnetic field on realistic bifurcated right coronary artery hemodynamics

Fractional ﬂow reserve derived from computed tomography decreases across severe coronary stenosis. The diagnostic accuracy of fractional ﬂow reserve-derived computed tomography is high for severe coronary stenosis. In this report, we present a case of no signiﬁcant fractional ﬂow reserve-derived computed tomography changes even in severe coronary stenosis. A 75-year-old man showed severe stenosis (85% diameter stenosis) in the distal segment of the right coronary artery on both computed tomography angiography and invasive coronary angiography. However, fractional ﬂow reserve-derived from computed tomography showed no signiﬁcant changes from the proximal (0.97) to the distal (0.95) segments despite the presence of severe stenotic lesion. This patient had diﬀerent features including the presence of a large acute marginal branch and signiﬁcantly lower plaque components in the stenotic lesion compared with another patient who had coronary stenosis in the same segment. A large bifurcation branch and/or proportion of plaque components can aﬀect fractional ﬂow reserve-derived from computed tomography hemodynamics.

Impact of Plaque Components on Fractional Flow Reserve-Derived Computed Tomography in Severe Coronary Stenosis.

Coronary computed tomography angiography (CCTA) and CT-derived fractional flow reserve (FFR CT ) provide high diagnostic accuracy for coronary artery disease (CAD), consistent with invasive coronary angiography (ICA), the gold standard diagnostic technique.The presence of calcified components, however, complicates the interpretation of coronary stenosis severity.We present a case where there was a discrepant assessment of coronary stenosis severity between CCTA/FFR CT (indicating significant obstructive CAD) and ICA (showing no apparent obstructive CAD).CCTA/FFR CT revealed that the stenotic lesion, located in the middle segment of the left circumflex artery, was surrounded by plaque components.The proximal and distal portions of the stenotic lesion consisted of 80.9% luminal volume, 0.2% low-attenuation plaque, 13.4% intermediate-attenuation plaque, and 5.5% calcified plaque.In contrast, the stenotic lesion itself contained 50.0%luminal volume, 0.3% low-attenuation plaque, 26.7% intermediateattenuation plaque, and 22.9% calcified plaque.Invasive coronary angiography showed no apparent obstructive CAD, implying that the lesions appearing as significant obstructive CAD on CCTA/FFR CT were likely overestimated due to the effects of extravascular calcified plaque.Advanced extravascular calcified plaque surrounding the lesion may cause several artifacts (such as blooming and/or beam hardening artifacts) and/or vasodilator dysfunction (either organic and/or functional), potentially leading to an overestimation of the severity of coronary stenosis in CCTA/FFR CT assessments. 

pdf/impact-of-advanced-extravascular-calcified-plaque-on-the-2nbx6i29x3.pdf

Impact of Advanced Extravascular Calcified Plaque on the Assessment of Coronary Stenosis Severity

Background: The common and potentially fatal disorder known as coronary artery disease (CAD) is characterised by turbulent and sluggish blood flow at the coronary artery bifurcation site, particularly at broader angles. Curved multiplanar reformat (CMPR) and 3D volume rendering (3D VR) techniques could help in prediction of CAD. Objective: The aim of the current study was to evaluate of the capability of Multi-detector CT (MDCT) coronary angiography to quantify coronary bifurcation angles for early preventative treatment or preprocedural planning for coronary intervention. Patients and methods: Using a 128-detectors scanner, 60 patients with typical or atypical chest discomfort or failed catheterization received MDCT coronary angiography to characterise coronary anatomy. Coronary bifurcation angles were calculated using specialised software and post-processing methods for correlation with CAD severity. Results: Compared to the 3D VR approach, the CMPR technique revealed wider values of coronary bifurcation angles. However, Bland-Altman plots showed that both methods may be alternatively used. Because a wider angle was linked to a greater degree of stenosis, LAD-LCX angle differed significantly between individuals with significant and nonsignificant CAD. Conclusion: Measurements of various coronary bifurcation angles, particularly the LAD-LCX angle, which is thought to be a predictor for CAD, can be made using MDCT coronary angiographic examination with CMPR and 3D VR methods. More plaques are likely to form when the angle is wider.

https://ejhm.journals.ekb.eg/article_305782_09ea3b0ce51e1d631074ec0bac29459e.pdf

Role of Multidetector Computed Tomography Coronary Angiography in Evaluation of Coronary Bifurcation Angles as a Predictor of Coronary Artery Disease

Abstract Objectives Computed tomography (CT) derived fractional flow reserve (FFR CT ) decreases from the proximal to the distal part due to a variety of factors. The energy loss due to the bifurcation angle may potentially contribute to a progressive decline in FFR CT . However, the association of the bifurcation angle with FFR CT is still not entirely understood. This study aimed to investigate the impact of various bifurcation angles on FFR CT decline below the clinically crucial relevance of 0.80 in vessels with no apparent coronary artery disease (CAD). Methods A total of 83 patients who underwent both CT angiography including FFR CT and invasive coronary angiography, exhibiting no apparent CAD were evaluated. ΔFFR CT was defined as the change in FFR CT from the proximal to the distal in the left anterior descending artery (LAD) and left circumflex artery (LCX). The bifurcation angle was calculated from three-dimensional volume rendered images. Vessel morphology and plaque characteristics were also assessed. Results ΔFFR CT significantly correlated with the bifurcation angle (LAD angle, r = 0.35, p = 0.001; LCX angle, r = 0.26, p = 0.02) and vessel length (LAD angle, r = 0.30, p = 0.005; LCX angle, r = 0.49, p &lt; 0.0001). In LAD, vessel length was the strongest predictor for distal FFR CT of ≤ 0.80 ( β -coefficient = 0.55, p = 0.0003), immediately followed by the bifurcation angle (β-coefficient = 0.24, p = 0.02). The bifurcation angle was a good predictor for a distal FFR CT ≤ 0.80 (LAD angle, cut-off 31.0°, AUC 0.70, sensitivity 74%, specificity 68%; LCX angle, cut-off 52.6°, AUC 0.86, sensitivity 88%, specificity 85%). Conclusions In vessels with no apparent CAD, vessel length was the most influential factor on FFR CT , directly followed by the bifurcation angle. Key Points • Both LAD and LCX bifurcation angles are factors influencing FFR CT . • Bifurcation angle is one of the predictors of a distal FFR CT of ≤ 0.80 and an optimal cut-off value of 31.0° for the LAD and 52.6° for the LCX. • Bifurcation angle should be taken into consideration when interpreting numerical values of FFR CT . 

/pdf/impact-of-coronary-bifurcation-angle-on-computed-tomography-ew6g3ngp.pdf

Impact of coronary bifurcation angle on computed tomography derived fractional flow reserve in coronary vessels with no apparent coronary artery disease


 
 
 Type of funding sources: None.
 
 
 
 Computed-tomography (CT) derived fractional-flow-reserve (FFRCT) decreases from the proximal to the distal part of vessel due to the influence of various factors. The energy loss due to the bifurcation angle may potentially contribute to a progressive FFRCT decline. However, the association of the bifurcation angle with FFRCT is still not entirely understood.
 
 
 
 This study aimed to investigate the impact of various bifurcation angles on FFRCT decline below the clinically crucial pathological value of 0.80 in normal coronary arteries.
 
 
 
 A total of 83 consecutive patients who underwent both CT angiography including FFRCT and invasive coronary angiography, resulting in normal coronary arteries were evaluated. ΔFFRCT was defined as the magnitude of the change in FFRCT from the proximal to the distal vessel in the left anterior descending (LAD) and left circumflex (LCX). Both LAD angle and LCX bifurcation angle were measured as the crossing angle between the centrelines of the left main trunk and each coronary artery (LAD or LCX) on the 3-dimensional volume rendered image of the coronary artery tree (Figure 1). Vessel length, lumen volume, non-calcified plaque volume, and calcified plaque volume were assessed.
 
 
 
 Bifurcation angle was significantly lower in LAD angle (LAD angle, 31.1 ± 6.6°; LCX angle, 42.8 ± 14.9°, p < 0.0001). FFRCT showed a continuous gradual decline from the proximal to the distal in both LAD (from 0.95 ± 0.03 to 0.81 ± 0.06) and LCX (from 0.96 ± 0.03 to 0.88 ± 0.06). ΔFFRCT was significantly greater in LAD angle (LAD angle, 0.13 ± 0.06; LCX angle, 0.08 ± 0.05, p < 0.0001) ΔFFRCT was significantly correlated with each bifurcation angle (LAD angle, r = 0.35, p = 0.001; LCX angle, r = 0.26, p = 0.02) and vessel length (LAD angle, r = 0.30, p = 0.005; LCX angle, r = 0.49, p < 0.0001) (Figure 2A). In LAD, vessel length was the strongest predictor for distal FFRCT of ≤ 0.80 (β-coefficient = 0.56, p = 0.0002), immediately followed by the bifurcation angle (β-coefficient = 0.24, p = 0.02). The bifurcation angle was a good predictor for a distal FFRCT ≤ 0.80 (LAD angle, cut-off 31.0°, AUC 0.70, 95% CI 0.58–0.83, sensitivity 74%, specificity 68%; LCX angle, cut-off 52.6°, AUC 0.86, 95% CI 0.76–0.96, sensitivity 88%, specificity 85%) (Figure 2B).
 
 
 
 The change in FFRCT depended on the bifurcation angle. In normal coronary arteries, vessel length was the most influential factor on FFRCT, immediately followed by the bifurcation angle.


/pdf/impact-of-left-coronary-artery-bifurcation-angle-on-computed-8ackttxl.pdf

Impact of left coronary artery bifurcation angle on computed tomography derived fractional flow reserve in normal coronary artery disease

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

H. Devos

Author Tools

Chat about Author

Papers

Impact of coronary bifurcation angle on computed tomography derived fractional flow reserve in coronary vessels with no apparent coronary artery disease

Impact of left coronary artery bifurcation angle on computed tomography derived fractional flow reserve in normal coronary artery disease