Read by QxMD icon Read

Modelling heart valve growth

Peter E Hammer, Erin G Roberts, Sitaram M Emani, Pedro J Del Nido
OBJECTIVES: Neither heart valve repair methods nor current prostheses can accommodate patient growth. Normal aortic and pulmonary valves have 3 leaflets, and the goal of valve repair and replacement is typically to restore normal 3-leaflet morphology. However, mammalian venous valves have bileaflet morphology and open and close effectively over a wide range of vessel sizes. We propose that they might serve as a model for pediatric heart valve reconstruction and replacement valve design...
August 31, 2016: Journal of Thoracic and Cardiovascular Surgery
Tilly Eldridge, Łukasz Łangowski, Nicola Stacey, Friederike Jantzen, Laila Moubayidin, Adrien Sicard, Paul Southam, Richard Kennaway, Michael Lenhard, Enrico S Coen, Lars Østergaard
Fruits exhibit a vast array of different 3D shapes, from simple spheres and cylinders to more complex curved forms; however, the mechanism by which growth is oriented and coordinated to generate this diversity of forms is unclear. Here, we compare the growth patterns and orientations for two very different fruit shapes in the Brassicaceae: the heart-shaped Capsella rubella silicle and the near-cylindrical Arabidopsis thaliana silique. We show, through a combination of clonal and morphological analyses, that the different shapes involve different patterns of anisotropic growth during three phases...
September 15, 2016: Development
Daniel Alejandro Lerman, Sai Prasad, Nasri Alotti
OBJECTIVE: Denosumab is a fully human monoclonal antibody and novel antiresorptive agent that works by binding receptor activator of nuclear factor kappa-β ligand (RANKL) and inhibiting the signaling cascade that causes osteoclast maturation, activity, and survival. We aimed to elucidate the effect of Denosumab in the process of spontaneous and induced calcification in an in vitro porcine valvular interstitial cells (VICs) model. MATERIALS AND METHODS: VICs were extracted from fresh porcine hearts by serial collagenase digestion...
January 3, 2016: International Journal of Cardiovascular Research
Fraser D Rubens, Yen-Yen Gee, Janet M C Ngu, Li Chen, Ian G Burwash
OBJECTIVES: We sought to assess the effect of 2 contemporary pericardial valves on left ventricular mass regression and clinical outcomes after aortic valve replacement (AVR) in patients with aortic stenosis (AS). METHODS: Patients were followed postoperatively in a dedicated valve clinic. A propensity score was derived for each patient and used to adjust all analyses. Longitudinal analysis was performed using a repeated measures growth curve model. Survival analysis was assessed with a Cox proportional hazards model...
June 18, 2016: Journal of Thoracic and Cardiovascular Surgery
Ling Qiuyang, Wu Ting, Ye Ting, Su Zhaoliang, Zong Gangjun
OBJECTIVE: To establish human heart valve interstitial cells calcification culture model in vitro, and observe the effect of bone morphogenetic protein-2 (BMP-2) on calcification of human heart valve interstitial cells. METHODS: Human heart valve interstitial cells were cultured in vitro, and divided into control group: cells were cultured in conventional media plus recombinant human BMP-2 treatment and experimental group: besides above treaments, calcification inducers ( recombinant human BMP-2, β-glycerophosphate, L-ascorbic acid, dexamethasone) were added to the culture media...
August 2015: Zhonghua Xin Xue Guan Bing za Zhi
Mehdi Jahandardoost, Guy Fradet, Hadi Mohammadi
To date, to the best of the authors' knowledge, in almost all of the studies performed around the hemodynamics of bileaflet mechanical heart valves, a heart rate of 70-72 beats/min has been considered. In fact, the heart rate of ~72 beats/min does not represent the entire normal physiological conditions under which the aortic or prosthetic valves function. The heart rates of 120 or 50 beats/min may lead to hemodynamic complications, such as plaque formation and/or thromboembolism in patients. In this study, the hemodynamic performance of the bileaflet mechanical heart valves in a wide range of normal and physiological heart rates, that is, 60-150 beats/min, was studied in the opening phase...
March 2016: Proceedings of the Institution of Mechanical Engineers. Part H, Journal of Engineering in Medicine
Yusuke Sakamoto, Rachel M Buchanan, Michael S Sacks
Heart valve interstitial cells (VICs) play a critical role in the maintenance and pathophysiology of heart valve tissues. Normally quiescent in the adult, VICs can become activated in periods of growth and disease. When activated, VICs exhibit increased levels of cytokines and extracellular matrix (ECM) synthesis, and upregulated expression and strong contraction of α-smooth muscle actin (α-SMA) fibers. However, it remains unknown how expression and contraction of the α-SMA fibers, which vary among different VIC types, contribute to the overall VIC mechanical responses, including the nucleus and cytoskeleton contributions...
February 2016: Journal of the Mechanical Behavior of Biomedical Materials
Apinya Bharmanee, Kathleen Zelin, Yamuna Sanil, Pooja Gupta, Peter P Karpawich
BACKGROUND: Standard, 5-7-Fr diameter pacing leads (PLs) can adversely affect atrioventricular valve (AVV) and venous (superior vena cava [SVC], innominate [INN]) integrities. Although chronic pacing/sensing performances have been reported on the steroid-eluting, lumenless, 4.1-Fr PL (Model 3830, Medtronic Inc., Minneapolis, MN, USA), comparative valve and venous effects are largely unknown. METHODS: Patients (n = 134) were divided into two PL groups: Group 1 (n = 65, Model 3830) and Group 2 (n = 69, various 5-7 Fr models) and followed up to 9 years postimplant...
November 2015: Pacing and Clinical Electrophysiology: PACE
Daniel S Puperi, Liezl R Balaoing, Ronan W O'Connell, Jennifer L West, K Jane Grande-Allen
Physiologically relevant in vitro models are needed to study disease progression and to develop and screen potential therapeutic interventions for disease. Heart valve disease, in particular, has no early intervention or non-invasive treatment because there is a lack of understanding the cellular mechanisms which lead to disease. Here, we establish a novel, customizable synthetic hydrogel platform that can be used to study cell-cell interactions and the factors which contribute to valve disease. Spatially localized cell adhesive ligands bound in the scaffold promote cell growth and organization of valve interstitial cells and valve endothelial cells in 3D co-culture...
October 2015: Biomaterials
Elodie Mintet, Emilie Rannou, Valérie Buard, Gail West, Olivier Guipaud, Georges Tarlet, Jean-Christophe Sabourin, Marc Benderitter, Claudio Fiocchi, Fabien Milliat, Agnès François
The endothelial-to-mesenchymal transition (EndoMT) is a crucial cellular process during heart development necessary to the formation of cardiac valves. This embryonic process reappears in several pathological situations, such as vascular injury or organ fibrosis of various etiologies, as a mediator of extracellular matrix-producing cells. Because radiation induces both vascular damage and fibrosis, we investigated whether radiation exposure induces EndoMT in primary human intestinal microvascular endothelial cells (HIMECs) and whether EndoMT contributes to radiation-induced rectal damage in humans and in a preclinical model of radiation proctitis in mice...
September 2015: American Journal of Pathology
Zahra Vahabi, Rasool Amirfattahi
Aorta is formed in a dynamic environment which gives rise to imbalances between many forces that tend to extend the diameter and length. Furthermore, internal forces tend to resist this extension. Impedance tomography can show this imbalance to stimulate the stenosis of aortic valve, growth of the elastic, collagen and to effectively reduce the stresses in the underlying tissue. In blood flow, auscultation noises occurred and in the echocardiography decrease in left ventricular ejection speed can be observed...
April 2015: Journal of Medical Signals and Sensors
Shogo Shimada, Christian Robles, Ben M W Illigens, Alejandra M Casar Berazaluce, Pedro J del Nido, Ingeborg Friehs
BACKGROUND: Endocardial fibroelastosis (EFE), characterized by a diffuse endocardial thickening through collagen and elastin fibers, develops in the human fetal heart restricting growth of the left ventricle (LV). Recent advances in fetal imaging indicate that EFE development is directly associated with a distended, poorly contractile LV in evolving hypoplastic left heart syndrome (HLHS). In this study, we developed an animal model of EFE by introducing this human fetal LV morphopathology to an immature rat heart...
2015: BioMed Research International
Brian R Lindman, Jared G Breyley, Joel D Schilling, Anna M Vatterott, Alan Zajarias, Hersh S Maniar, Ralph J Damiano, Marc R Moon, Jennifer S Lawton, Brian F Gage, Marc A Sintek, Alejandro Aquino, Christopher L Holley, Neil M Patel, Cassandra Lawler, John M Lasala, Eric Novak
OBJECTIVE: In heart failure populations without aortic stenosis (AS), the prognostic utility of multiple biomarkers in addition to clinical factors has been demonstrated. We aimed to determine whether multiple biomarkers of cardiovascular stress are associated with mortality in patients with AS undergoing aortic valve replacement (AVR) independent of clinical factors. METHODS: From a prospective registry of patients with AS, 345 participants who were referred for and treated with AVR (transcatheter (n=183) or surgical (n=162)) were included...
September 2015: Heart: Official Journal of the British Cardiac Society
Boyang Su, Foad Kabinejadian, Hui Qun Phang, Gideon Praveen Kumar, Fangsen Cui, Sangho Kim, Ru San Tan, Jimmy Kim Fatt Hon, John Carson Allen, Hwa Liang Leo, Liang Zhong
This work presents a numerical simulation of intraventricular flow after the implantation of a bileaflet mechanical heart valve at the mitral position. The left ventricle was simplified conceptually as a truncated prolate spheroid and its motion was prescribed based on that of a healthy subject. The rigid leaflet rotation was driven by the transmitral flow and hence the leaflet dynamics were solved using fluid-structure interaction approach. The simulation results showed that the bileaflet mechanical heart valve at the mitral position behaved similarly to that at the aortic position...
2015: PloS One
Francis E Smit, Pascal M Dohmen
Abstract Tissue engineering was introduced by Vacanti and Langer in the 80's, exploring the potential of this new technology starting with the well-known "human ear on the mouse back". The goal is to create a substitute which supplies an individual therapy for patients with regeneration, remodeling and growth potential. The growth potential of these subjects is of special interest in congenital cardiac surgery, avoiding repeated interventions and surgery. Initial applications of tissue engineered created substitutes were relatively simple cardiovascular grafts seeded initially by end-differentiated autologous endothelial cells...
2015: Medical Science Monitor Basic Research
Arash Kheradvar, Elliott M Groves, Lakshmi P Dasi, S Hamed Alavi, Robert Tranquillo, K Jane Grande-Allen, Craig A Simmons, Boyce Griffith, Ahmad Falahatpisheh, Craig J Goergen, Mohammad R K Mofrad, Frank Baaijens, Stephen H Little, Suncica Canic
As the first section of a multi-part review series, this section provides an overview of the ongoing research and development aimed at fabricating novel heart valve replacements beyond what is currently available for patients. Here we discuss heart valve replacement options that involve a biological component or process for creation, either in vitro or in vivo (tissue-engineered heart valves), and heart valves that are fabricated from polymeric material that are considered permanent inert materials that may suffice for adults where growth is not required...
April 2015: Annals of Biomedical Engineering
Jennifer K Redig, Gameil T Fouad, Darcie Babcock, Benjamin Reshey, Eleanor Feingold, Roger H Reeves, Cheryl L Maslen
Atrioventricular septal defects (AVSD) are highly heritable, clinically significant congenital heart malformations. Genetic and environmental modifiers of risk are thought to work in unknown combinations to cause AVSD. Approximately 5-10% of simplex AVSD cases carry a missense mutation in CRELD1. However, CRELD1 mutations are not fully penetrant and require interactions with other risk factors to result in AVSD. Vascular endothelial growth factor-A (VEGFA) is a well-characterized modulator of heart valve development...
2014: AIMS Genetics
Madeline Midgett, Sandra Rugonyi
Embryonic heart formation results from a dynamic interplay between genetic and environmental factors. Blood flow during early embryonic stages plays a critical role in heart development, as interactions between flow and cardiac tissues generate biomechanical forces that modulate cardiac growth and remodeling. Normal hemodynamic conditions are essential for proper cardiac development, while altered blood flow induced by surgical manipulations in animal models result in heart defects similar to those seen in humans with congenital heart disease...
2014: Frontiers in Physiology
Cora Lueders, Ben Jastram, Roland Hetzer, Hartmut Schwandt
Three-dimensional (3D) printing technologies have reached a level of quality that justifies considering rapid manufacturing for medical applications. Herein, we introduce a new approach using 3D printing to simplify and improve the fabrication of human heart valve scaffolds by tissue engineering (TE). Custom-made human heart valve scaffolds are to be fabricated on a selective laser-sintering 3D printer for subsequent seeding with vascular cells from human umbilical cords. The scaffolds will be produced from resorbable polymers that must feature a number of specific properties: the structure, i...
October 2014: European Journal of Cardio-thoracic Surgery
Bo Qian, Ran Mo, Min Da, Wei Peng, Yuanli Hu, Xuming Mo
Congenital heart disease (CHD) is the most common birth defect in humans. The genetic causes of sporadic CHD remain largely unknown. Bone morphogenetic protein 4 (BMP4), a member of the transforming growth factor-β (TGF-β) family, is required for normal heart development. Loss of BMP4 gene expression in mice is associated with septal defects, defective endocardial cushion remodeling, and abnormal semilunar valve formation. This study evaluated the contribution of single nucleotide polymorphisms (SNPs) in BMP4 to CHD susceptibility in a case-control study of 575 patients with CHD and 844 non-CHD control subjects in a Chinese population...
December 2014: Pediatric Cardiology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"