Am J Physiol Heart Circ Physiol
January 2025
Background And Purpose: Thrombectomy in distal, medium vessels is a topic of increasing interest. To date, there are few studies focused on performance of ≤5F catheters in medium vessels. The purpose of this study is to compare the performance of the 3F, 4F, and 5F MIVI Neuroscience Q Catheters versus Penumbra 3F, 4F, and MicroVention Sofia 5F Catheters.
View Article and Find Full Text PDFIntroduction: Passive leg raise (PLR) is a simple, dynamic maneuver that has been used to increase preload to the heart. We hypothesize that PLR may offer a new and efficient office-based tool for assessing blood pressure (BP) control in older adults.
Methods: One hundred and three veterans (≥60 years old) without known cardiovascular disease and varying degrees of blood pressure control were included in this cross-sectional cohort study.
Biomech Model Mechanobiol
December 2024
Pulmonary hypertension (PH) is a debilitating disease that alters the structure and function of both the proximal and distal pulmonary vasculature. This alters pressure-flow relationships in the pulmonary arterial and venous trees, though there is a critical knowledge gap in the relationships between proximal and distal hemodynamics in disease. Multiscale computational models enable simulations in both the proximal and distal vasculature.
View Article and Find Full Text PDFPulmonary artery stenosis (PAS) often presents in children with congenital heart disease, altering blood flow and pressure during critical periods of growth and development. Variability in stenosis onset, duration, and severity result in variable growth and remodeling of the pulmonary vasculature. Computational fluid dynamics (CFD) models enable investigation into the hemodynamic impact and altered mechanics associated with PAS.
View Article and Find Full Text PDFAm J Physiol Heart Circ Physiol
August 2024
Computational, or in silico, models are an effective, noninvasive tool for investigating cardiovascular function. These models can be used in the analysis of experimental and clinical data to identify possible mechanisms of (ab)normal cardiovascular physiology. Recent advances in computing power and data management have led to innovative and complex modeling frameworks that simulate cardiovascular function across multiple scales.
View Article and Find Full Text PDFWhile cardiac output reserve with exercise predicts outcomes in cardiac and pulmonary vascular disease, precise quantification of exercise cardiac output requires invasive cardiopulmonary testing (iCPET). To improve the accuracy of cardiac output reserve estimation with transthoracic echocardiography (TTE), this prospective study aims to define changes in right ventricular outflow tract diameter (RVOTd) with exercise and its relationship with invasively measured haemodynamics. Twenty subjects underwent simultaneous TTE and iCPET, with data collected at rest, leg-raise, 25 W, 50 W ( = 16), 75 W ( = 14), and 100 W ( = 6).
View Article and Find Full Text PDFPulmonary hypertension is a cardiovascular disorder manifested by elevated mean arterial blood pressure (>20 mmHg) together with vessel wall stiffening and thickening due to alterations in collagen, elastin, and smooth muscle cells. Hypoxia-induced (type 3) pulmonary hypertension can be studied in animals exposed to a low oxygen environment for prolonged time periods leading to biomechanical alterations in vessel wall structure. This study introduces a novel approach to formulating a reduced order nonlinear elastic structural wall model for a large pulmonary artery.
View Article and Find Full Text PDFBiomech Model Mechanobiol
April 2024
Chronic thromboembolic pulmonary hypertension (CTEPH) develops due to the accumulation of blood clots in the lung vasculature that obstructs flow and increases pressure. The mechanobiological factors that drive progression of CTEPH are not understood, in part because mechanical and hemodynamic changes in the small pulmonary arteries due to CTEPH are not easily measurable. Using previously published hemodynamic measurements and imaging from a large animal model of CTEPH, we applied a subject-specific one-dimensional (1D) computational fluid dynamic (CFD) approach to investigate the impact of CTEPH on pulmonary artery stiffening, time-averaged wall shear stress (TAWSS), and oscillatory shear index (OSI) in extralobar (main, right, and left) pulmonary arteries and intralobar (distal to the extralobar) arteries.
View Article and Find Full Text PDFThe left (LV) and right (RV) ventricles are linked biologically, hemodynamically, and mechanically, a phenomenon known as ventricular interdependence. While LV function has long been known to impact RV function, the reverse is increasingly being realized to have clinical importance. Investigating ventricular interdependence clinically is challenging given the invasive measurements required, including biventricular catheterization, and confounding factors such as comorbidities, volume status, and other aspects of subject variability.
View Article and Find Full Text PDFComputational hemodynamics models are becoming increasingly useful in the management and prognosis of complex, multiscale pathologies, including those attributed to the development of pulmonary vascular disease. However, diseases like pulmonary hypertension are heterogeneous, and affect both the proximal arteries and veins as well as the microcirculation. Simulation tools and the data used for model calibration are also inherently uncertain, requiring a full analysis of the sensitivity and uncertainty attributed to model inputs and outputs.
View Article and Find Full Text PDFChronic thromboembolic pulmonary hypertension (CTEPH) develops due to the accumulation of blood clots in the lung vasculature that obstruct flow and increase pressure. The mechanobiological factors that drive progression of CTEPH are not understood, in part because mechanical and hemodynamic changes in the pulmonary vasculature due to CTEPH are not easily measurable. Using previously published hemodynamic measurements and imaging from a large animal model of CTEPH, we developed a subject-specific one-dimensional (1D) computational fluid dynamic (CFD) models to investigate the impact of CTEPH on pulmonary artery stiffening, time averaged wall shear stress (TAWSS), and oscillatory shear index (OSI).
View Article and Find Full Text PDFComputational models provide an efficient paradigm for integrating and linking multiple spatial and temporal scales. However, these models are difficult to parameterize and match to experimental data. Recent advances in both data collection and model analyses have helped overcome this limitation.
View Article and Find Full Text PDFComputational models provide an efficient paradigm for integrating and linking multiple spatial and temporal scales. However, these models are difficult to parameterize and match to experimental data. Recent advances in both data collection and model analyses have helped overcome this limitation.
View Article and Find Full Text PDFCombined pre-/postcapillary pulmonary hypertension (Cpc-PH), a complication of left heart failure, is associated with higher mortality rates than isolated postcapillary pulmonary hypertension alone. Currently, knowledge gaps persist on the mechanisms responsible for the progression of isolated postcapillary pulmonary hypertension (Ipc-PH) to Cpc-PH. Here, we review the biomechanical and mechanobiological impact of left heart failure on pulmonary circulation, including mechanotransduction of these pathological forces, which lead to altered biological signaling and detrimental remodeling, driving the progression to Cpc-PH.
View Article and Find Full Text PDFChronic stimulation of cardiac α-adrenergic receptors (α-ARs) improves symptoms in multiple preclinical models of heart failure. However, the translational significance remains unclear. Human engineered heart tissues (EHTs) provide a means of quantifying the effects of chronic α-AR stimulation on human cardiomyocyte physiology.
View Article and Find Full Text PDFBackground: Exercise-induced changes in arterial function could contribute to a hypertensive response to exercise (HRE) in older individuals. We performed the present analysis to define the acute arterial stiffness response to exercise in ambulatory older adults.
Methods: Thirty-nine Veterans (>60 years old), without known cardiovascular disease, participated in this study, including 19 Veterans who were hypertensive (70.
In-vivo studies of pulmonary vascular disease and pulmonary hypertension (PH) have provided key insight into the progression of right ventricular (RV) dysfunction. Additional in-silico experiments using multiscale computational models have provided further details into biventricular mechanics and hemodynamic function in the presence of PH, yet few have assessed whether model parameters are practically identifiable prior to data collection. Moreover, none have used modeling to devise synergistic experimental designs.
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