Effects of ventricular pacing on finite deformation in canine left ventricles

1987 ◽  
Vol 252 (5) ◽  
pp. H1023-H1030 ◽  
Author(s):  
L. K. Waldman ◽  
J. W. Covell
Keyword(s):  
Left Ventricle ◽  
Finite Deformation ◽  
Repeated Measures ◽  
Three Dimensional ◽  
Radial Strain ◽  
Tangent Plane ◽  
Ventricular Pacing ◽  
Anesthetized Dogs ◽  
Principal Directions ◽  
Heart Wall

Despite the fact that myofibers would be expected to shorten only along their axes, there is now evidence for substantial deformation away from the local myofiber direction in the left ventricle. To determine if the principal directions of deformation could be altered by a physiological stimulus, we examined local three-dimensional finite deformation in the anterior free wall of the left ventricle during normal atrial activation (AA) and, subsequently, during epicardial ventricular pacing (VP) at the site of deformation measurement in open-chest anesthetized dogs. An analysis of variance by repeated measures revealed the following significant changes (P less than or equal to 0.05) in the overall (average of epicardial and endocardial data) strain variables at end systole. Circumferential strain increased from -0.07 (AA) to 0.14 (VP), radial strain decreased from 0.16 (AA) to 0.01 (VP), shear in the tangent plane of the local epicardium decreased from 0.04 (AA) to -0.02 (VP), shear in the plane of the longitudinal and radial coordinates decreased from 0.03 (AA) to -0.03 (VP). Neither the first (greatest shortening) nor the third (greatest lengthening) principal strain changed significantly, but the direction of the first principal axis of deformation projected on the epicardial tangent plane changed from -51 degrees (AA) to -80 degrees (VP) from circumferential. In addition, substantial tipping of the plane of principal shortening away from the epicardial tangent plane was observed, particularly with ventricular pacing. These data indicate that the principal directions of deformation can be altered substantially by changing the activation sequence. In conjunction with the observed shearing deformations, particularly near the endocardium, they support the concept that locally the heart wall deforms as a unit with significant transmural tethering.

Comparison of two-dimensional and three-dimensional echocardiographic strain in children with CHD

2017 ◽  
Vol 27 (8) ◽  
pp. 1557-1565 ◽  
Author(s):  
Bethany L. Wisotzkey ◽  
Brian D. Soriano ◽  
Sujatha Buddhe
Keyword(s):  
Left Ventricle ◽  
Circumferential Strain ◽  
New Technology ◽  
Three Dimensional ◽  
Radial Strain ◽  
Strain Analysis ◽  
Left Ventricular ◽  
Two Dimensional ◽  
The Mean ◽  
Dimensional Echocardiography

AbstractBackgroundIn CHD, three-dimensional strain analysis may overcome limitations of Doppler and two-dimensional strain of the left ventricle. The aims of this study were to evaluate feasibility and reproducibility of three-dimensional longitudinal, circumferential, and radial systolic strain by three-dimensional speckle-tracking echocardiography compared with two-dimensional echocardiography.MethodsPatients with CHD, biventricular circulation with a systemic left ventricle, and who had two- and three-dimensional imaging performed on the same day from 2010 to 2014 were included. Quantitative two- and three-dimensional strain analyses were performed (two-dimensional cardiac performance analysis version 1.2 and four-dimensional left ventricular analysis version 3.1). Intra- and inter-observer variabilities were calculated on 25 studies.ResultsA total of 30 patients, including 19 (61%) males, with a median age of 3.6 years (0.1–22 years) were included. The mean fractional shortening was 34.6±5.3%, and the mean ejection fraction was 62.0±6.4%. Measurement of two- and three-dimensional strain was feasible in >95% of segments. Good correlation was observed between longitudinal and circumferential strain (r=0.92, p⩽0.001 and r=0.87, p⩽0.001), but not radial strain (r=0.29, p=0.2). Intra- and inter-observer agreements were better for three-dimensional compared with two-dimensional strain, and better for both two- and three-dimensional longitudinal and circumferential strains compared with radial strain.ConclusionLeft ventricular three-dimensional strain analysis is feasible in children with CHD. The reproducibility of longitudinal and circumferential strain by three-dimensional analyses is better. Further longitudinal studies are warranted for the potential clinical application of this new technology.

scholarly journals Myocardial deformation in patients with a single left ventricle using 2D cardiovascular magnetic resonance feature tracking: a case–control study

2021 ◽  
Author(s):  
Fabian Strodka ◽  
Jana Logoteta ◽  
Roman Schuwerk ◽  
Mona Salehi Ravesh ◽  
Dominik Daniel Gabbert ◽  
...  
Keyword(s):  
Cardiovascular Magnetic Resonance ◽  
Magnetic Resonance ◽  
Left Ventricle ◽  
Feature Tracking ◽  
Systolic Function ◽  
Radial Strain ◽  
Left Ventricular ◽  
Lv Function ◽  
Significant Difference ◽  
Lv Volumes

AbstractVentricular dysfunction is a well-known complication in single ventricle patients in Fontan circulation. As studies exclusively examining patients with a single left ventricle (SLV) are sparse, we assessed left ventricular (LV) function in SLV patients by using 2D-cardiovascular magnetic resonance (CMR) feature tracking (2D-CMR-FT) and 2D-speckle tracking echocardiography (2D-STE). 54 SLV patients (11.4, 3.1–38.1 years) and 35 age-matched controls (12.3, 6.3–25.8 years) were included. LV global longitudinal, circumferential and radial strain (GLS, GCS, GRS) and strain rate (GLSR, GCSR, GRSR) were measured using 2D-CMR-FT. LV volumes, ejection fraction (LVEF) and mass were determined from short axis images. 2D-STE was applied in patients to measure peak systolic GLS and GLSR. In a subgroup analysis, we compared double inlet left ventricle (DILV) with tricuspid atresia (TA) patients. The population consisted of 19 DILV patients, 24 TA patients and 11 patients with diverse diagnoses. 52 patients were in NYHA class I and 2 patients were in class II. Most SLV patients had a normal systolic function but median LVEF in patients was lower compared to controls (55.6% vs. 61.2%, p = 0.0001). 2D-CMR-FT demonstrated reduced GLS, GCS and GCSR values in patients compared to controls. LVEF correlated with GS values in patients (p < 0.05). There was no significant difference between GLS values from 2D-CMR-FT and 2D-STE in the patient group. LVEF, LV volumes, GS and GSR (from 2D-CMR-FT) were not significantly different between DILV and TA patients. Although most SLV patients had a preserved EF derived by CMR, our results suggest that, LV deformation and function may behave differently in SLV patients compared to healthy subjects.

scholarly journals Automatic 3D dense phenotyping provides reliable and accurate shape quantification of the human mandible

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Pieter-Jan Verhelst ◽  
H. Matthews ◽  
L. Verstraete ◽  
F. Van der Cruyssen ◽  
D. Mulier ◽  
...  
Keyword(s):  
Repeated Measures ◽  
Intraclass Correlation ◽  
Three Dimensional ◽  
Correlation Coefficients ◽  
Surface Registration ◽  
Anatomical Landmarks ◽  
Centroid Size ◽  
Intraclass Correlation Coefficients ◽  
Total Variability ◽  
Automatic Phenotyping

AbstractAutomatic craniomaxillofacial (CMF) three dimensional (3D) dense phenotyping promises quantification of the complete CMF shape compared to the limiting use of sparse landmarks in classical phenotyping. This study assesses the accuracy and reliability of this new approach on the human mandible. Classic and automatic phenotyping techniques were applied on 30 unaltered and 20 operated human mandibles. Seven observers indicated 26 anatomical landmarks on each mandible three times. All mandibles were subjected to three rounds of automatic phenotyping using Meshmonk. The toolbox performed non-rigid surface registration of a template mandibular mesh consisting of 17,415 quasi landmarks on each target mandible and the quasi landmarks corresponding to the 26 anatomical locations of interest were identified. Repeated-measures reliability was assessed using root mean square (RMS) distances of repeated landmark indications to their centroid. Automatic phenotyping showed very low RMS distances confirming excellent repeated-measures reliability. The average Euclidean distance between manual and corresponding automatic landmarks was 1.40 mm for the unaltered and 1.76 mm for the operated sample. Centroid sizes from the automatic and manual shape configurations were highly similar with intraclass correlation coefficients (ICC) of > 0.99. Reproducibility coefficients for centroid size were < 2 mm, accounting for < 1% of the total variability of the centroid size of the mandibles in this sample. ICC’s for the multivariate set of 325 interlandmark distances were all > 0.90 indicating again high similarity between shapes quantified by classic or automatic phenotyping. Combined, these findings established high accuracy and repeated-measures reliability of the automatic approach. 3D dense CMF phenotyping of the human mandible using the Meshmonk toolbox introduces a novel improvement in quantifying CMF shape.

scholarly journals P946 Right atrial volumetric and functional analysis by three-dimensional speckle-tracking echocardiography in acromegaly

2020 ◽  
Vol 21 (Supplement_1) ◽  
Author(s):  
A Kormanyos ◽  
A Kalapos ◽  
P Domsik ◽  
N Gyenes ◽  
N Ambrus ◽  
...  
Keyword(s):  
Speckle Tracking ◽  
Speckle Tracking Echocardiography ◽  
Three Dimensional ◽  
Radial Strain ◽  
Human Growth ◽  
Active Phase ◽  
Right Atrial ◽  
Control Group ◽  
Cardiovascular Comorbidities ◽  
Atrial Contraction

Abstract Introduction Acromegaly is a chronic, rare hormonal disease associated with major cardiovascular comorbidities. The disease, in the majority of the cases, is caused by a benign human growth hormone secreting adenoma. Cardiovascular involvement is especially common in acromegaly patients from the most common hypertension to cardiomyopathy. It was set out to quantify right atrial (RA) morphology and function in a group of acromegaly patients using three-dimensional (3D) speckle-tracking echocardiography (3DSTE). Methods The study comprised 30 patients from which 8 patients were excluded due to inadequate image quality. Mean age of the remaining acromegaly patients were 53.7 ± 14.5 years (7 males). Ten patients were in active phase, while 12 subjects had inactive acromegaly. In the control group 40 healthy adults were enrolled (mean age: 52.3 ± 8.2 years, 15 males). In each case, complete two-dimensional Doppler echocardiography was performed followed by 3DSTE. Results Maximum (54.5 ± 14.4 ml vs. 47.2 ± 11.6 ml, p &lt;0.05) and minimum (35.5 ± 10.2 ml vs. 29.2 ± 9.1 ml, p &lt;0.05) RA volumes and RA volume before atrial contraction (45.1 ± 11.1 ml vs. 38.2 ± 10.3 ml, p &lt;0.05) were significantly higher in case of acromegaly compared to the healthy controls. Both global and mean segmental peak 3D strain (-11.94 ± 7.52% vs. -8.07 ± 5.03%, p &lt;0.05 and -17.16 ± 6.13% vs. -13.78 ± 5.35%, p &lt;0.05) were higher in the acromegaly group compared to the controls. At atrial contraction, mean segmental radial strain (-13.22 ± 6.45% vs. -9.74 ± 4.58%, p &lt;0.05) was significantly higher and mean segmental 3D strain (-9.78 ± 5.44% vs. -13.78 ± 5.35%, p &lt;0.05) was significantly lower in the acromegaly group compared to the controls. Between the active and inactive group of acromegaly patients, mean segmental longitudinal strain (28.17 ± 4.89% vs. 35.34 ± 9.75%, p &lt;0.05) was significantly different. Numerous independent strain parameters had significant correlations with different hormonal variables in the active acromegaly group. These correlations were not present in the inactive acromegaly subgroup. Conclusion Acromegaly is associated with significant RA volumetric and functional abnormalities.

Three-dimensional active shape model matching for left ventricle segmentation in cardiac CT

2003 ◽  
Author(s):  
Hans C. van Assen ◽  
Rob J. van der Geest ◽  
Mikhail G. Danilouchkine ◽  
Hildo J. Lamb ◽  
Johan H. C. Reiber ◽  
...  
Keyword(s):  
Left Ventricle ◽  
Cardiac Ct ◽  
Three Dimensional ◽  
Active Shape Model ◽  
Model Matching ◽  
Shape Model ◽  
Active Shape ◽  
Ventricle Segmentation

scholarly journals Long-term prognostic significance of three-dimensional echocardiographic parameters of the left ventricle and left atrium

2009 ◽  
Vol 11 (3) ◽  
pp. 250-256 ◽  
Author(s):  
S. Caselli ◽  
E. Canali ◽  
M. L. Foschi ◽  
D. Santini ◽  
E. Di Angelantonio ◽  
...  
Keyword(s):  
Left Ventricle ◽  
Left Atrium ◽  
Prognostic Significance ◽  
Three Dimensional ◽  
Echocardiographic Parameters

Education Committee Best Paper of 1995 Award: Methods of Classical Mechanics Applied to Turbulence Stresses in a Tip Leakage Vortex

1996 ◽  
Vol 118 (4) ◽  
pp. 622-629 ◽  
Author(s):  
J. G. Moore ◽  
S. A. Schorn ◽  
J. Moore
Keyword(s):  
Stress Tensor ◽  
Reynolds Stress ◽  
Classical Mechanics ◽  
Three Dimensional ◽  
Surface Model ◽  
Reynolds Stresses ◽  
Tip Leakage Vortex ◽  
Tip Leakage ◽  
Stress Tensors ◽  
Principal Directions

Moore et al. measured the six Reynolds stresses in a tip leakage vortex in a linear turbine cascade. Stress tensor analysis, as used in classical mechanics, has been applied to the measured turbulence stress tensors. Principal directions and principal normal stresses are found. A solid surface model, or three-dimensional glyph, for the Reynolds stress tensor is proposed and used to view the stresses throughout the tip leakage vortex. Modeled Reynolds stresses using the Boussinesq approximation are obtained from the measured mean velocity strain rate tensor. The comparison of the principal directions and the three-dimensional graphic representations of the strain and Reynolds stress tensors aids in the understanding of the turbulence and what is required to model it.

scholarly journals Targeting in Virtual Workspaces: motor learning consolidates spatial memory for performance clusters

2019 ◽  
Author(s):  
Bradly Alicea ◽  
Corey Bohil ◽  
Frank Biocca ◽  
Charles Owen
Keyword(s):  
Repeated Measures ◽  
Target Location ◽  
Movement Time ◽  
Three Dimensional ◽  
Arm Movement ◽  
Hierarchical Cluster ◽  
Movement Speed ◽  
Advantages And Disadvantages ◽  
Training Interval ◽  
Speed And Accuracy

Our objective was to focus on linkages between the process of learning and memory and the placement of objects within an array of targets in a virtual workspace. Participants were instructed to place virtual objects serially within a three-dimensional target array. One phase presented each target sequentially, and required participants to make timed ballistic arm movements. The other phase presented all nine targets simultaneously, which required ballistic arm movement towards the correct target location as recalled from the learning phase. Movement time and accuracy were assessed using repeated-measures ANOVA, a hierarchical cluster analysis, and a multiple linear regression. Collectively, this revealed numerous speed and accuracy advantages and disadvantages for various positional combinations. Upper positions universally yielded longer movement times and larger error measurements. Individual ability for mental rotation combined with task learning over a fixed training interval was found to predict accuracy for specific locations. The prediction that location influences movement speed and accuracy was supported, but with some caveats. These results may be particularly useful in the design of instructor stations and other hybrid physical-virtual workspaces.

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