scholarly journals Transmural distribution of three-dimensional strain in the isolated arrested canine left ventricle

1991 ◽  
Vol 261 (3) ◽  
pp. H918-H928 ◽  
Author(s):  
J. H. Omens ◽  
K. D. May ◽  
A. D. McCulloch
Keyword(s):  
Three Dimensional ◽  
Left Ventricular Pressure ◽  
Ventricular Volume ◽  
Left Ventricular ◽  
Fiber Direction ◽  
Plane Shear ◽  
Left Handed ◽  
Longitudinal Strains ◽  
Transverse Shear Strains ◽  
Principal Strains

Three-dimensional myocardial strains in seven isolated, potassium-arrested dog hearts were measured by biplane radiography of 3 transmural columns of 4-6 radiopaque beads implanted in the midanterior left ventricular free wall. Transmural distributions of strain during inflation of a left ventricular balloon to 20-30 mmHg were computed with respect to the zero pressure state. Magnitudes of the 3 principal strains increased in proportion to ventricular volume (0.0088, 0.0037, and -0.0059 ml-1). At a left ventricular pressure of 8 +/- 4 mmHg, mean circumferential (E11) and longitudinal strains (E22) were similar, increasing from epicardium (0.058 +/- 0.055 and 0.036 +/- 0.024) to subendocardium (0.139 +/- 0.102 and 0.120 +/- 0.084) as did the transmural (wall thinning) strain E33 (-0.053 +/- 0.071 to -0.128 +/- 0.083). Negative in-plane shear E12 was small (-0.008 to -0.052), consistent with a left-handed torsion of the left ventricular wall. Mean transverse shear strains E13 and E23 were small (-0.029 to 0.007) but showed considerable variability between hearts. Fiber strain had no significant transmural variation (P = 0.57). The principal axis of greatest strain was close to the fiber orientation on the epicardium (-15 degrees) but closer to the cross-fiber direction near the endocardium (-40 degrees). Therefore, the end-diastolic fiber lengths are maximized on the epicardium and minimized on the endocardium.

Abstract 964: Effect of Volume Overload on Left Ventricular Torsion and Extra Cellular Matrix

Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Hosakote M Nagaraj ◽  
Thomas S Denney ◽  
Steven G Lloyd ◽  
David Calhoun ◽  
Inmaculada Aban ◽  
...  
Keyword(s):  
Picric Acid ◽  
Three Dimensional ◽  
Volume Overload ◽  
Left Ventricular ◽  
Deformation Model ◽  
Data Set ◽  
Left Ventricular Torsion ◽  
Tissue Tagging ◽  
Ventricular Torsion ◽  
Longitudinal Strains

Background: Muscle fibers are arranged in a spiral network and are connected by extracellular matrix (ECM). LV torsion is increased in the pressure overloaded heart where there is an increase in ECM. However, torsion and its relation to ECM have not been systematically studied in the volume overloaded heart. Hypothesis: The volume overloaded heart has a decrease in LV torsion due a loss of ECM. Methods: Primary mitral regurgitation (MR) (n=29), resistant hypertension (HTN) (n=77) and normal volunteers (NL) (n±37) were studied. Comprehensive cardiac magnetic resonance imaging (MRI) with tissue tagging was performed and analyzed using three-dimensional data set. Torsion was computed by fitting a B-spline deformation model in prolate-spheroidal coordinates to the tag line data. A subset of MR subjects had LV collagen assessed by picric acid Sirius red from biopsy samples taken at the time of surgery. Results: LV ejection fraction was 65% in MR and 70% in HTN. MR demonstrated eccentric remodeling and HTN demonstrated concentric remodeling. HTN had significantly higher torsion angle and systolic twist compared to NL and MR. This was associated with a simultaneous decrease in longitudinal strain. In contrast, MR patients had similar torsion indices, circumferential and longitudinal strains compared to NL. LV biopsy in MR demonstrated a decrease in interstitial collagen compared to NL. Conclusions: As opposed to the pure volume overloaded heart, LV torsional forces are increased in the pressure overloaded heart. This difference may be related to a rearrangement of the laminar structure due to a differential effect on ECM in the volume overloaded versus the pressure overloaded heart.

Abstract 224: A Deep Learning Approach to Left-Ventricular Chamber Quantification for Fully Automated Three Dimensional Strain Analysis in Cardiotoxicity

2020 ◽  
Vol 127 (Suppl_1) ◽  
Author(s):  
Bryant M Baldwin ◽  
Shane Joseph ◽  
Xiaodong Zhong ◽  
Ranya Kakish ◽  
Cherie Revere ◽  
...  
Keyword(s):  
Deep Learning ◽  
Interpolation Method ◽  
Three Dimensional ◽  
Strain Analysis ◽  
Correlation Coefficients ◽  
Semantic Segmentation ◽  
Left Ventricular ◽  
Breast Cancer Patients ◽  
Left Ventricular Chamber ◽  
Longitudinal Strains

This study investigated MRI and semantic segmentation-based deep-learning (SSDL) automation for left-ventricular chamber quantifications (LVCQ) and low longitudinal strain (LLS) determination, thus eliminating user-bias by providing an automated tool to detect cardiotoxicity (CT) in breast cancer patients treated with antineoplastic agents. Displacement Encoding with Stimulated Echoes-based (DENSE) myocardial images from 26 patients were analyzed with the tool’s Convolution Neural Network with underlying Resnet-50 architecture. Quantifications based on the SSDL tool’s output were for LV end-diastolic diameter (LVEDD), ejection fraction (LVEF), and mass (LVM) (see figure for phase sequence). LLS was analyzed with Radial Point Interpolation Method (RPIM) with DENSE phase-based displacements. LVCQs were validated by comparison to measurements obtained with an existing semi-automated vendor tool (VT) and strains by 2 independent users employing Bland-Altman analysis (BAA) and interclass correlation coefficients estimated with Cronbach’s Alpha (C-Alpha) index. F1 score for classification accuracy was 0.92. LVCQs determined by SSDL and VT were 4.6 ± 0.5 vs 4.6 ± 0.7 cm (C-Alpha = 0.93 and BAA = 0.5 ± 0.5 cm) for LVEDD, 58 ± 5 vs 58 ± 6 % (0.90, 1 ± 5%) for LVEF, 119 ± 17 vs 121 ± 14 g (0.93, 5 ± 8 g) for LV mass, while LLS was 14 ± 4 vs 14 ± 3 % (0.86, 0.2 ± 6%). Hence, equivalent LV dimensions, mass and strains measured by VT and DENSE imaging validate our unique automated analytic tool. Longitudinal strains in patients can then be analyzed without user bias to detect abnormalities for the indication of cardiotoxicity and the need for therapeutic intervention even if LVEF is not affected.

scholarly journals Rapid online quantification of left ventricular volume from real-time three-dimensional echocardiographic data

2005 ◽  
Vol 27 (4) ◽  
pp. 460-468 ◽  
Author(s):  
Lawrence D. Jacobs ◽  
Ivan S. Salgo ◽  
Sascha Goonewardena ◽  
Lynn Weinert ◽  
Patrick Coon ◽  
...  
Keyword(s):  
Real Time ◽  
Left Ventricular Volume ◽  
Three Dimensional ◽  
Ventricular Volume ◽  
Left Ventricular
Sign in / Sign up

Export Citation Format

Share Document