Comparative measurement of cardiac cycle by means of different sensors

2017 ◽  
Author(s):  
Eiko Priidel ◽  
Raul Land ◽  
Veljo Sinivee ◽  
Paul Annus ◽  
Mart Min
Keyword(s):  
Cardiac Cycle ◽  
Comparative Measurement

Comparative Measurement Properties of Constant Work-Rate Cycling and Endurance Shuttle Walking in Patients with COPD: Data from the TORRACTO Study

Pneumologie ◽  
2018 ◽  
Vol 72 (S 01) ◽  
pp. S90-S90
Author(s):  
K Siemon ◽  
F Maltais ◽  
DE O'Donnell ◽  
A Hamilton ◽  
Y Zhao ◽  
...  
Keyword(s):  
Work Rate ◽  
Measurement Properties ◽  
Comparative Measurement ◽  
Constant Work Rate

Assessment of Myocardial Viability in Persistent Defects on Thallium-201 SPECT after Reinjection Using Gradient-Echo MRI

1996 ◽  
Vol 35 (05) ◽  
pp. 146-152 ◽  
Author(s):  
A. Kögler ◽  
H.-A. Schmitt ◽  
D. Emrich ◽  
H. Kreuzer ◽  
D. L. Munz ◽  
...  
Keyword(s):  
Wall Thickness ◽  
Myocardial Viability ◽  
Cardiac Cycle ◽  
Single Photon ◽  
Contractile Function ◽  
Left Ventricular ◽  
Wall Thickening ◽  
Gradient Echo ◽  
Systolic Wall Thickening

SummaryThis prospective study assessed myocardial viability in 30 patients with coronary heart disease and persistent defects despite reinjection on TI-201 single-photon computed tomography (SPECT). In each patient, three observers graded TI-201 uptake in 7 left ventricular wall segments. Gradient-echo magnetic resonance imaging in the region of the persistent defect generated 12 to 16 short axis views representing a cardiac cycle. A total of 120 segments were analyzed. Mean end-diastolic wall thickness and systolic wall thickening (± SD) was 11.5 ± 2.7 mm and 5.8 ± 3.9 mm in 48 segments with normal TI-201 uptake, 10.1 ± 3.4 mm and 3.7 ± 3.1 mm in 31 with reversible lesions, 11.3 ± 2.8 mm and 3.3 ± 1.9 mm in 10 with mild persistent defects, 9.2 ± 2.9 mm and 3.2 ±2.2 mm in 15 with moderate persistent defects, 5.8 ± 1.7 mm and 1.3 ± 1.4 mm in 16 with severe persistent defects, respectively. Significant differences in mean end-diastolic wall thickness (p <0.0005) and systolic wall thickening (p <0.005) were found only between segments with severe persistent defects and all other groups, but not among the other groups. On follow-up in 11 patients after revascularization, 6 segments with mild-to-moderate persistent defects showed improvement in mean systolic wall thickening that was not seen in 6 other segments with severe persistent defects. These data indicate that most myocardial segments with mild and moderate persistent TI-201 defects after reinjection still contain viable tissue. Segments with severe persistent defects, however, represent predominantly nonviable myocardium without contractile function.

Mathematical myocardium elasticity properties modeling in echocardiography study of diastolic and systolic function of the left ventricle (Preprint)

2020 ◽  
Author(s):  
Lucian Popescu ◽  
Nelu-Mihai Trofenciuc ◽  
Simina Crisan ◽  
Aurora Diana Bordejevic ◽  
Alexandru Mischie ◽  
...  
Keyword(s):  
Left Ventricle ◽  
Cardiac Cycle ◽  
Systolic Function ◽  
Study Group ◽  
Mathematical Approach ◽  
Energetic Approach ◽  
Elasticity Property ◽  
Property Modeling ◽  
Coefficient Of Elasticity ◽  
Mechanical Movement

BACKGROUND A systematic and quantitative comparative analysis for this subject has not been done so far. Thus defined, the coefficient of elasticity is a whole new dimension. OBJECTIVE This study proposes a new mathematical myocardium elasticity property modeling in characterizing of the ventricular diastole and systole. METHODS The study group consisted of 2283 consecutive patients evaluated by echocardiography. The mathematical approach is made starting from energetic consideration, by applying the energy conservation low for the blood entering from left atrium into left ventricle during diastole period. RESULTS Analyzing all the data obtained we developed two brand new coefficients to describe the cardiac cycle and we had verified if the coefficients are correlated with classically used parameters. We consider that the energetic approach take into consideration the whole mechanical movement that is happening inside the heart and can offer a very synthetic and scientific solid view about the cardiac cycle. CONCLUSIONS The new coefficients are simply to be calculated and as you will see from our research the correlation with other classically used parameters is obvious. The direct physical approach of blood flow within the heart can generate new, beneficial perspectives in diagnosing various heart conditions, or even in understanding how works the filling of the ventricles and atria during a heartbeat.

An under‐recognized phenomenon: Myocardial volume change during the cardiac cycle

2021 ◽  
Author(s):  
Vinayak Kumar ◽  
Armando Manduca ◽  
Chaitanya Rao ◽  
Alexander J. Ryu ◽  
Raymond J. Gibbons ◽  
...  
Keyword(s):  
Volume Change ◽  
Cardiac Cycle

scholarly journals Slithering CSF: Cerebrospinal Fluid Dynamics in the Stationary and Moving Viper Boa, Candoia aspera

Biology ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 672
Author(s):  
Bruce A. Young ◽  
Skye Greer ◽  
Michael Cramberg
Keyword(s):  
Cerebrospinal Fluid ◽  
Cardiac Cycle ◽  
Low Frequency ◽  
Mean Amplitude ◽  
The Body ◽  
Body Waves ◽  
Lower Amplitude ◽  
Lateral Undulation ◽  
Recovery From Anesthesia ◽  
The Relationship

In the viper boa (Candoia aspera), the cerebrospinal fluid (CSF) shows two stable overlapping patterns of pulsations: low-frequency (0.08 Hz) pulses with a mean amplitude of 4.1 mmHg that correspond to the ventilatory cycle, and higher-frequency (0.66 Hz) pulses with a mean amplitude of 1.2 mmHg that correspond to the cardiac cycle. Manual oscillations of anesthetized C. aspera induced propagating sinusoidal body waves. These waves resulted in a different pattern of CSF pulsations with frequencies corresponding to the displacement frequency of the body and with amplitudes greater than those of the cardiac or ventilatory cycles. After recovery from anesthesia, the snakes moved independently using lateral undulation and concertina locomotion. The episodes of lateral undulation produced similar influences on the CSF pressure as were observed during the manual oscillations, though the induced CSF pulsations were of lower amplitude during lateral undulation. No impact on the CSF was found while C. aspera was performing concertina locomotion. The relationship between the propagation of the body and the CSF pulsations suggests that the body movements produce an impulse on the spinal CSF.

Dynamics of the right atrio-ventricular junction in human: a spatial high-resolution study with multiphase computed tomography

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
J Jouan ◽  
I Masari ◽  
V Bliah ◽  
G Soulat ◽  
D Craiem ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Cardiac Cycle ◽  
Cardiac Computed Tomography ◽  
Reconstruction Method ◽  
Imaging Data ◽  
High Definition ◽  
Vertical Projection ◽  
Horizontal Projection ◽  
Cross Sectional ◽  
The Right

Abstract Introduction In order to improve knowledge of the tricuspid valve (TV) function and its coupling with the right atrio-ventricular junction (RAVJ) and right ventricle (RV), new four-dimensional high-definition imagery methods are mandatory (3D+t). Purpose Using an innovative reconstruction method based on multiphase cardiac computed tomography imaging (4D-MCCTI), we finely analyzed the morphological & dynamical features of tricuspid annulus (TA) and RAVJ components in order to assess new functional parameters of TV and RV functions. Methods Volume imaging data sets through time were obtained from 4D-MCCTI of 30 subjects (sex ratio 1, mean age 57±11y.) with no rhythm, valvular or ventricular abnormalities on echocardiography and implemented in a custom software for 3D semi-automated delineation of 18 points around TA perimeter. Coordinates of these points in each of the 10 time-phases within an RR interval were used to calculate specific geometrical features of TA such as 3D/2D areas, perimeters, 360°-diameters and vertical deformation. Subsequently, RV and Right Atrium (RA) inner contours were also delineated (Figure). Results TA shape was elliptical in horizontal projection with a mean eccentricity index (EcI) of 0.58±0.12; and saddle-shapped in vertical projection with a horn nearby the antero-septal commissure. This feature remained throughout the cardiac cycle but TA was more planar (minimal TA-height: 4.47±1.04 mm) and circular (minimal EcI=0.44±0.14) in mid-diastole when TA-3Darea and TA-3Dperimeter reached a maximum of 6.98±1.21 cm2/m2 and 7.41±0.91 cm, respectively. Correlation between TA-3Darea, TA-2Darea and latero-septal diameter (LSD) were R2=0.99 and R2=0.73, respectively. LSD was minimal in early-systole (18.83±3.04 mm/m2) and maximal in mid-diastole (20.04±3.05 mm/m2). Correlation of TA-3Darea with RV and RA cross-sectional areas were R2=0.82 and R2=0.71, respectively. Conversely, there was no significant correlation between TA, RV and RA concentric contractions. Conclusions Our method for 4D-MTCCI analysis has allowed confirming the shape and dynamics function of RAVJ throughout the cardiac cycle in healthy subjects, and giving new reference parameters for TV and RV evaluation. Software multiplanar view of TA Funding Acknowledgement Type of funding source: None

The durations of the phases and periods of the cardiac cycle in athletes as dependent on the specific type of training

2007 ◽  
Vol 33 (6) ◽  
pp. 720-726
Author(s):  
V. N. Prokof’eva ◽  
V. I. Kuznetsov ◽  
A. A. Korenevskaya
Keyword(s):  
Cardiac Cycle
Sign in / Sign up

Export Citation Format

Share Document