Background: The perinatal transition's impact on systemic right ventricle (SRV) cardiac hemodynamics is not fully understood. Standard clinical image analysis tools fall short of capturing comprehensive diastolic and systolic measures of these hemodynamics.
Objectives: Compare standard and novel hemodynamic echocardiogram (echo) parameters to quantify perinatal changes in SRV and healthy controls.
The effects of pressure drop across cardiac valve cushion regions and endocardial wall strain in the early developmental stages of a teleost species heart are poorly understood. In the presented work, we utilize microscale particle image velocimetry (μPIV) flow measurements of developing medaka hearts from 3 to 14 dpf (n = 5 at each dpf) to quantify the pressure field and endocardial wall strain. Peak pressure drop at the atrioventricular canal (ΔPAVC) and outflow tract (ΔPOFT) show a steady increase with fish age progression.
View Article and Find Full Text PDFObjective: We present a novel method for detecting atrial fibrillation (AFib) by analyzing Lead II electrocardiograms (ECGs) using a unique set of features.
Methods: For this purpose, we used specific signal processing techniques, such as proper orthogonal decomposition, continuous wavelet transforms, discrete cosine transform, and standard cross-correlation, to extract 48 features from the ECGs. Thus, our approach aims to more effectively capture AFib signatures, such as beat-to-beat variability and fibrillatory waves, than traditional metrics.
Platelets are central to thrombosis. Research at the intersection of biological and physical sciences provides proof-of-concept for shear rate-dependent platelet slip at vascular stenosis and near device surfaces. Platelet slip extends the observed biological "slip-bonds" to the boundary of functional gliding without contact.
View Article and Find Full Text PDFObjectives: The objective of our study was to semiautomatically generate echocardiogram indices in pediatric sepsis using novel algorithms and determine which indices were associated with mortality. We hypothesized that strain and diastolic indices would be most associated with mortality. Design: Retrospective cohort study of children with sepsis from 2017 to 2022.
View Article and Find Full Text PDFBackground: 4D flow magnetic resonance imaging (4D flow MRI) can assess and measure the complex flow patterns of the right ventricle (RV) in congenital heart diseases, but its limited availability makes the broad application of intracardiac flow assessment challenging. Color Doppler imaging velocity reconstruction from conventional echocardiography is an emerging alternative, but its validity against 4D flow MRI needs to be established.
Objective: To compare intracardiac flow parameters measured by color Doppler velocity reconstruction (DoVeR) against parameters measured from 4D flow MRI.
Background: Determinants of exercise intolerance in a phenotype of heart failure with preserved ejection fraction (HFpEF) with normal left ventricular (LV) structure have not been fully elucidated.
Methods: Cardiopulmonary exercise testing and exercise-stress echocardiography were performed in 44 HFpEF patients without LV hypertrophy. Exercise capacity was determined by peak oxygen consumption (peak VO).
We present a new method for measuring global longitudinal strain and global longitudinal strain rate from 2D echocardiograms using a logarithmic-transform correlation (LTC) method. Traditional echocardiography strain analysis depends on user inputs and chamber segmentation, which yield increased measurement variability. In contrast, our approach is automated and does not require cardiac chamber segmentation and regularization, thus eliminating these issues.
View Article and Find Full Text PDFWe present a user-initialized, automated left ventricle (LV) segmentation method for use with echocardiograms (echo). The method uses an iterative Dijkstra's algorithm, strategic node selection, and novel cost matrix formulation based on intensity peak prominence and is termed the "Prominence Iterative Dijkstra's" algorithm, or ProID. ProID is initialized with three user-input clicks per time-series scan.
View Article and Find Full Text PDFA new approach to calculating left ventricular (LV) early filling propagation velocity (VP) from color M-mode echocardiograms using wavelet analysis is described. Current methods for measuring VP do not account for the spatiotemporal variation in VP. They are confined by empirical assumptions and user inputs that hinder the accuracy of VP, limiting its clinical utility.
View Article and Find Full Text PDFWe introduce a new method (ppler locity econstruction or DoVeR), for reconstructing two-component velocity fields from colour Doppler scans. DoVeR employs the streamfunction-vorticity equation, which satisfies mass conservation while accurately approximating the flow rate of rotation. We validated DoVeR using artificial colour Doppler images generated from computational fluid dynamics models of left ventricle (LV) flow.
View Article and Find Full Text PDFWe present clinical measurements and a theoretical model for the decay of the left ventricular (LV) vortex ring. Previous works have postulated that the formation of the vortex ring downstream of the mitral annulus is affected by LV diastolic impairment. However, no previous works have considered how the strength of the vortex ring will decay inside the ventricle after its formation.
View Article and Find Full Text PDFRecent applications of computational fluid dynamics (CFD) applied to the cardiovascular system have demonstrated its power in investigating the impact of hemodynamics on disease initiation, progression, and treatment outcomes. Flow metrics such as pressure distributions, wall shear stresses (WSS), and blood velocity profiles can be quantified to provide insight into observed pathologies, assist with surgical planning, or even predict disease progression. While numerous studies have performed simulations on clinical human patient data, it often lacks prediagnosis information and can be subject to large intersubject variability, limiting the generalizability of findings.
View Article and Find Full Text PDFA new processing method for echocardiographic particle image velocimetry (EchoPIV) using moving ensemble (ME) correlation with dynamic phase correlation filtering was developed to improve velocity measurement accuracy for routine clinical evaluation of cardiac function. The proposed method was tested using computationally generated echocardiogram images. Error analysis indicated that ME EchoPIV yields a twofold improvement in bias and random error over the current standard correlation method (β = -0.
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