scholarly journals Nodal Analysis for Coronary Artery Ischemia Diagnosis

2020 ◽  
Author(s):  
Samuel Freitas ◽  
Gabriel Ramos ◽  
Jean Schmith ◽  
Cristiano Costa
Keyword(s):  
Blood Flow ◽  
Coronary Artery ◽  
Fractional Flow ◽  
Circumflex Artery ◽  
Nodal Analysis ◽  
Left Circumflex Artery ◽  
Flow Reserve ◽  
Novel Approach ◽  
Local Impact ◽  
Quantitative Flow Ratio

A cardiac ischemia is a restriction of the blood flow in the heart muscle caused by narrowed heart arteries. The most common narrowing process is called atherosclerosis. The strategies to evaluate its significance are the Fractional Flow Reserve (FFR) and the Quantitative Flow Ratio (QFR) which evaluate the local impact of the atherosclerosis. This work presents a novel approach for ischemia diagnosis based on linear nodal analysis, which enables the evaluation of the whole coronary system. Even with limited variables, this method is able to indicate and quantify the impacts of a stenosis in other coronary segments than the constricted artery itself. Empirical results have shown that a left coronary artery (LCA) stenosis increases the blood flow in the left circumflex artery (LCX) together with a normal flow decrease in the left main stem (LMS), which provides secondary narrowing impact evidences. These results can complement the current techniques and increase the diagnosis assertiveness.

13N-ammonia PET/CT stress myocardial blood flow compared to fractional flow reserve in coronary artery disease

2020 ◽  
Vol 41 (2) ◽  
pp. 133-138 ◽  
Author(s):  
Jouke J. Boer ◽  
Johan J.J.S. Kappelhof ◽  
Friso M. van der Zant ◽  
Maurits Wondergem ◽  
Hans(J) B.R.M. de Swart ◽  
...  
Keyword(s):  
Coronary Artery Disease ◽  
Blood Flow ◽  
Coronary Artery ◽  
Myocardial Blood Flow ◽  
Fractional Flow Reserve ◽  
Fractional Flow ◽  
Flow Reserve ◽  
Stress Myocardial Blood Flow ◽  
Pet Ct ◽  
Artery Disease

scholarly journals Malignant Arrhythmia in Acute Conus Artery Occlusion

2021 ◽  
pp. 1-4
Author(s):  
Lucian Calmac ◽  
◽  
Ruxandra-Nicoleta Horodinschi ◽  
Keyword(s):  
Coronary Artery ◽  
Right Coronary Artery ◽  
Distal Segment ◽  
Artery Occlusion ◽  
Fractional Flow ◽  
Circumflex Artery ◽  
Flow Reserve ◽  
Malignant Arrhythmia ◽  
Significant Life ◽  
The Right

We present the case of a 74 y.o. woman with multiple cardiovascular risk factors, admitted for worsening angina over the past three weeks. On admission she had no significant electrocardiographic and echocardiographic changes and a negative Troponin test. Coronary angiography revealed single vessel disease: severe stenosis of the right coronary artery (RCA) ostium (difficult to assess visually), 50% mid-vessel and 60% distal segment. The left anterior descending artery and circumflex artery had non-significant stenoses. Fractional flow reserve technique (FFR) was used to evaluate the RCA ostial lesion which proved to be significant, therefore angioplasty with three drug-eluting stents was performed for all three lesions of the right coronary artery, starting from the ostium. Due to its location, minimal aortic protrusion of the first stent occluded a small ostial branch which proved to be the conus artery and the patient developed mild transient angina during the procedure, but with good outcome regarding the intracoronary flow. After the angioplasty the patient presented anterior leads ST-elevation and developed mild chest pain with an increase in cardiac enzymes (CK-MB peak 39 U/L). Later on, she had two episodes of ventricular fibrillation with rapid defibrillation to sinus rhythm, with no further events or echocardiographic changes and no recurrent angina. The patient was started on amiodarone to prevent ventricular arrhythmias and continued double antiplatelet therapy with aspirin and clopidogrel. She was discharged six days later. In conclusion, although the conus branch is a small artery, its acute occlusion can have significant life-threatening complications.

scholarly journals Coronary Tortuosity Overestimate The FFR Measurement In Stenotic Coronary Artery Model

2021 ◽  
Author(s):  
Jiatong Liu ◽  
Libo Zhang ◽  
Hongzeng Xu
Keyword(s):  
Blood Flow ◽  
Coronary Artery ◽  
Fractional Flow Reserve ◽  
Three Dimensional ◽  
Pressure Profile ◽  
Measurement Procedure ◽  
Fractional Flow ◽  
Load Effect ◽  
Flow Reserve ◽  
Coronary Tortuosity

Abstract Background: The object of the study is to investigate the effect of coronary tortuosity (CT) on fractional flow reserve (FFR) in stenotic coronary artery.Methods: A three dimensional computational model of simulation of blood flow in stenotic coronary artery with multi-bend CT was constructed with Fluent 16.0 software. Blood was simulated as non-Newtonian fluid with the Carreau model. The simulation of blood flow in coronary artery stenotic model was used by the finite element methods with the condition of CT and no coronary tortuosity (NCT). Coronary artery hemodynamic parameters such as pressure, velocity and physiological diagnostic parameter fractional flow reserve (FFR) were studied in the model with the coronary tortuosity condition.Results: The results showed that the downstream CT impedance condition has significant impacts on numerical simulation. The pressure profile of pre-stenotic is almost identical in the two models. However the pressure in the pre-stenotic and post-stenotic artery domain is much higher in the CT model. The pressure fluctuation range in CT model was much higher than that in the NCT model. In the coronary artey model with 75% stenosis for the CT condition, the FFR was 0.823 while the FFR was 0.767 in the same model with NCT condition.Conclusions: This study provides evidence that FFR value was increased in coronary stenotic artery with the presence of CT. Therefore, it should be taking into account the influence of CT load effect in FFR measurement procedure, otherwise the CAD risk will be underestimated.

Angiography-based quantitative flow ratio versus fractional flow reserve in patients with coronary artery disease and severe aortic stenosis

2020 ◽  
Vol 16 (4) ◽  
pp. e285-e292 ◽  
Author(s):  
Hernán Mejía-Rentería ◽  
Luis Nombela-Franco ◽  
Jean-Michel Paradis ◽  
Mattia Lunardi ◽  
Joo Myung Lee ◽  
...  
Keyword(s):  
Coronary Artery Disease ◽  
Coronary Artery ◽  
Severe Aortic Stenosis ◽  
Flow Ratio ◽  
Fractional Flow ◽  
Flow Reserve ◽  
Artery Disease ◽  
Quantitative Flow Ratio ◽  
Ratio Versus ◽  
Quantitative Flow

Analysis of blood flow in the entire coronary arterial tree

2005 ◽  
Vol 289 (1) ◽  
pp. H439-H446 ◽  
Author(s):  
N. Mittal ◽  
Y. Zhou ◽  
C. Linares ◽  
S. Ung ◽  
B. Kaimovitz ◽  
...  
Keyword(s):  
Blood Flow ◽  
Coronary Artery ◽  
Coronary Blood Flow ◽  
Flow Distribution ◽  
Model Parameters ◽  
Coronary Perfusion ◽  
Arterial Tree ◽  
Circumflex Artery ◽  
Left Circumflex Artery ◽  
The Right

A hemodynamic analysis of coronary blood flow must be based on the measured branching pattern and vascular geometry of the coronary vasculature. We recently developed a computer reconstruction of the entire coronary arterial tree of the porcine heart based on previously measured morphometric data. In the present study, we carried out an analysis of blood flow distribution through a network of millions of vessels that includes the entire coronary arterial tree down to the first capillary branch. The pressure and flow are computed throughout the coronary arterial tree based on conservation of mass and momentum and appropriate pressure boundary conditions. We found a power law relationship between the diameter and flow of each vessel branch. The exponent is ∼2.2, which deviates from Murray’s prediction of 3.0. Furthermore, we found the total arterial equivalent resistance to be 0.93, 0.77, and 1.28 mmHg·ml−1·s−1·g−1 for the right coronary artery, left anterior descending coronary artery, and left circumflex artery, respectively. The significance of the present study is that it yields a predictive model that incorporates some of the factors controlling coronary blood flow. The model of normal hearts will serve as a physiological reference state. Pathological states can then be studied in relation to changes in model parameters that alter coronary perfusion.

scholarly journals Computed tomography-derived characterisation of pericoronary,epicardial and paracardial adipose tissue and its association with myocardial ischemia as assessed by computed and invasive fractional flow

2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
M Goeller ◽  
H Duncker ◽  
M Moshage ◽  
D Dey ◽  
D Bittner ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Adipose Tissue ◽  
Coronary Artery ◽  
Myocardial Ischemia ◽  
Multivariable Analysis ◽  
Fractional Flow ◽  
Circumflex Artery ◽  
Flow Reserve ◽  
Ct Attenuation ◽  
Significant Difference

Abstract Introduction Increased pericoronary adipose tissue (PCAT) computed tomography (CT) attenuation derived from coronary CT angiography (CTA) around the right coronary artery (RCA) reflects coronary inflammation and relates to cardiac mortality. Purpose We aimed to investigate the yet unclear association between CT-derived characterisation of different cardiac adipose tissue compartments and the presence of myocardial ischemia as assessed by fractional flow reserve (FFR). Methods 133 stable individuals (64 years, 74% male) with coronary artery disease (CAD) underwent CTA including computed FFR (FFR-CT) measurement followed by invasive angiography with FFR (invasive FFR) assessment. The CT attenuation (HU) and volume (mm3) of PCAT were quantified around the RCA (10 to 50 mm from RCA ostium), the proximal 40 mm of the left anterior descending artery (LAD) and the circumflex artery (LCX) with the help of semi-automated software. The per patient PCAT CT attenuation was calculated as followed: (PCAT CT attenuation of RCA+LAD+LCX)/3. Quantification of epicardial adipose tissue (EAT) and paracardial adipose tissue (PAT; all intrathoracic adipose tissue outside the pericardium) were performed in non-contrast cardiac CT data sets using a fully automated deep-learning based algorithm. Results Median FFR-CT was 0.86 [0.79, 0.91] and median invasive FFR was 0.87 [0.81, 0.93]. Patients with presence of myocardial ischemia (n=26) defined by a FFR-CT threshold of ≤0.75 showed a significant higher PCAT CT attenuation of RCA (−75.1 HU vs. −81.1 HU, p=0.011) and per patient (−74.5 HU vs. −77.7 HU, p=0.045) than individuals without myocardial ischemia (n=107). In multivariable analysis adjusted for age, BMI, gender and traditional risk factors, both RCA and per patient PCAT CT attenuation were significant predictors of myocardial ischemia as assessed by FFRCT ≤0.75. Between individuals with myocardial ischemia compared to individuals without myocardial ischemia there was no significant difference neither in the volume and CT attenuation of EAT and PAT nor in the PCAT volume of RCA, LAD, LCX and per patient PCAT volume. Conclusions Our observations suggest that PCAT CT attenuation instead of PCAT volume, EAT and PAT measures might be associated with the presence of myocardial ischemia as assessed by FFR. FUNDunding Acknowledgement Type of funding sources: Foundation. Main funding source(s): German Heart Foundation e.V.

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