An engineering analysis of myocardial fiber orientation in pig's left ventricle in systole

1966 ◽  
Vol 155 (4) ◽  
pp. 503-511 ◽  
Author(s):  
Daniel D. Streeter ◽  
David L. Bassett
Keyword(s):  
Left Ventricle ◽  
Fiber Orientation ◽  
Engineering Analysis ◽  
Myocardial Fiber

Fiber orientation in hypertrophied canine left ventricle

1979 ◽  
Vol 236 (3) ◽  
pp. H487-H493 ◽  
Author(s):  
T. E. Carew ◽  
J. W. Covell
Keyword(s):  
Left Ventricle ◽  
Aortic Stenosis ◽  
Arteriovenous Fistula ◽  
Fiber Orientation ◽  
Diastolic Pressure ◽  
Pressure Overload ◽  
Volume Overload ◽  
Maximum Diameter ◽  
Myocardial Fiber

Myocardial fiber orientation was examined in transmural specimens obtained at the maximum diameter of the left ventricle from five dogs with pressure-overload hypertrophy produced by aortic stenosis, six dogs with volume-overload hypertrophy due to an arteriovenous fistula, and six exercise-hypertrophied greyhounds trained for racing. Hearts arrested in diastole were fixed in situ while the operating end-diastolic pressure was maintained. Fiber orientation changed smoothly from about +60 degrees (with respect to the equator) at the endocardium to about -69 degrees at the epicardium. The majority of fibers near the midwall were oriented circumferentially. These findings are quite similar to those previously reported for normal dogs. In comparison to normals, the left ventricles from dogs with pressure-overload had an increase in longitudinally oriented fibers, i.e. fiber angles between -67.5 degrees and -90 degrees and between +67.5 degrees and +90 degrees; these fibers comprised 10.4 +/- 1.8% of the total fibers in dogs with aortic stenosis vs. 2.9 +/- 1.8% of total fibers in normal dogs (P less than 0.001). Neither the dogs with volume-overload hypertrophy nor exercise-trained animals were significantly different from normals.

Contrasting ischemic contraction patterns by zone and layer in canine myocardium

1982 ◽  
Vol 243 (6) ◽  
pp. H852-H855 ◽  
Author(s):  
S. Hattori ◽  
W. S. Weintraub ◽  
J. B. Agarwal ◽  
M. M. Bodenheimer ◽  
V. S. Banka ◽  
...  
Keyword(s):  
Coronary Artery ◽  
Left Ventricle ◽  
Fiber Orientation ◽  
Coronary Occlusion ◽  
Short Axis ◽  
Circumflex Coronary Artery ◽  
Left Circumflex Coronary Artery ◽  
Close Relationship ◽  
Canine Myocardium

The effect of graded coronary occlusion on myocardial shortening in different zones of the left ventricle is not clear. Therefore, in 15 dogs ultrasonic crystals were used to evaluate the effect of graded coronary occlusion on subendocardial and subepicardial contraction in both the left anterior descending coronary artery (LAD) and left circumflex coronary artery (Circ) distributions. Subepicardial shortening was evaluated along both the long and short axes. In the LAD zones, segment shortening decreased in parallel in the subendocardium and subepicardium. In the circumflex zone subendocardial and subepicardial long axis shortening fell off in parallel, while subepicardial short axis shortening fell off more rapidly. Thus there is a close relationship between endocardial and epicardial segment shortening following graded coronary occlusion. In the circumflex zone, however, fiber orientation may affect the measurement of segment motion.

Abstract 13732: Evaluation of the Mechanical Effect of Thickened IPS Derived Cardiomyocyte Patch on the Distressed Left Ventricle Using Cardiac Simulator “Ut-heart”

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Hirotada Masuda ◽  
Shigeru Miyagawa ◽  
Takumi Washio ◽  
Seiryo Sugiura ◽  
Jun-ichi Okada ◽  
...  
Keyword(s):  
Left Ventricle ◽  
Fiber Orientation ◽  
In Silico ◽  
Cell Sheet ◽  
Sheet Thickness ◽  
Mechanical Effect ◽  
Heart Model ◽  
Ips Cell ◽  
Lv Remodeling ◽  
Pumping Function

Introduction: iPS cell-derived cardiac cell sheet (iPS sheet) transplantation is expected to have both cytokine paracrine effect and mechanical effect on the failed heart. In order to clarify the latter effect, we utilized the cardiac simulator “UT-Heart” to quantitatively evaluate the improvement of pumping function of the left ventricle with myocardial infarction covered by the thickened iPS sheet in silico. The direct mechanical impact of iPS sheet with various thicknesses was calculated first, and then the remodeling effect of fiber orientation was investigated. Patient and Method: An infarcted heart model based on the actual patient’s data was created on the computer and an iPS sheet was virtually implanted under the following assumptions: (1) electrophysiologically synchronized with the underlying cardiac muscle, (2) covered the infarct area entirely, (3) the fiber orientation of sheet was parallel to that of the epicardial tissue when attached, (4) if remodeling occurs, the fiber orientations of myocardial tissue and the attached sheet change such that the contraction force and the fiber strains are homogenized in the heart. The UT-Heart simulation was performed while changing iPS sheet thickness from 1mm to 5mm. Results: The LVEF of 18.0 % at pre-implantation was improved to 18.5 % with 1 mm thickness, and 19.6 % with 5 mm thickness without remodeling assumption as shown in the left of the figure. If LV remodeling occurs, the LVEF was improved to 20.9 % with 1mm thickness and 22.8 % with 5mm thickness. The LVESP was 10 mmHg higher than that of pre-implantation even when 1mm thickness was implanted. Conclusion: The direct mechanical effect of the thickened iPS sheet on the distressed LV was quantitatively evaluated in silico. Because changes in fiber orientation have a significant impact on pumping function, the remodeling assumption used herein should be experimentally verified in the future.

scholarly journals A rule‐based method to model myocardial fiber orientation in cardiac biventricular geometries with outflow tracts

2019 ◽  
Vol 35 (4) ◽  
pp. e3185 ◽  
Author(s):  
Ruben Doste ◽  
David Soto‐Iglesias ◽  
Gabriel Bernardino ◽  
Alejandro Alcaine ◽  
Rafael Sebastian ◽  
...  
Keyword(s):  
Fiber Orientation ◽  
Myocardial Fiber ◽  
Rule Based

STRESSES AND STRAINS IN THE PASSIVE LEFT VENTRICLE

1996 ◽  
Vol 04 (04) ◽  
pp. 535-554 ◽  
Author(s):  
H.R. CHAUDHRY ◽  
B. BUKIET ◽  
T. FINDLEY ◽  
A.B. RITTER
Keyword(s):  
Left Ventricle ◽  
Residual Stresses ◽  
Diastolic Function ◽  
Fiber Orientation ◽  
Deformation Theory ◽  
Stress Gradient ◽  
Circumferential Stress ◽  
Equatorial Region ◽  
Hollow Cone ◽  
Lower Stress

In this paper, we estimate the stresses and strains from the equatorial region down to the apex of the heart by modeling the passive left ventricle as a frustrum of a thick hollow cone. Large deformation theory has been employed in this analysis. Furthermore, the effects of residual stresses and the anisotropy due to muscle fiber orientation have been included. It is observed that circumferential stress, which is the most important physiologically, decreases considerably at the endocardium and is more evenly distributed through the wall when residual stresses are taken into account. The stresses also decrease as we go from the equatorial region to the apex. Because heart muscles physically have residual stresses, the consequent lower stress gradient through the wall enhances the diastolic function of the left ventricle.

Dependence of local left ventricular wall mechanics on myocardial fiber orientation: A model study

1992 ◽  
Vol 25 (10) ◽  
pp. 1129-1140 ◽  
Author(s):  
P.H.M. Bovendeerd ◽  
T. Arts ◽  
J.M. Huyghe ◽  
D.H. van Campen ◽  
R.S. Reneman
Keyword(s):  
Fiber Orientation ◽  
Left Ventricular ◽  
Left Ventricular Wall ◽  
Ventricular Wall ◽  
Myocardial Fiber ◽  
Model Study

Mapping Myocardial Fiber Orientation Using Echocardiography-Based Shear Wave Imaging

2012 ◽  
Vol 31 (3) ◽  
pp. 554-562 ◽  
Author(s):  
Wei-Ning Lee ◽  
M. Pernot ◽  
M. Couade ◽  
E. Messas ◽  
P. Bruneval ◽  
...  
Keyword(s):  
Shear Wave ◽  
Fiber Orientation ◽  
Myocardial Fiber ◽  
Shear Wave Imaging ◽  
Wave Imaging
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