The work by Giulio Ceradini in explaining the mechanism of semilunar cardiac valve function

2011 ◽  
Vol 35 (2) ◽  
pp. 110-113 ◽  
Author(s):  
Diana Troiani ◽  
Ermanno Manni

Using an excised pig heart preparation with tubes, a manometer, and a visualizing apparatus, Giulio Ceradini, an Italian physiologist working in the years of 1871–1872 in Carl Ludwig's famous laboratory in Leipzig, Germany, illustrated the mechanism of closure of the semilunar valves. He was the first to conceive that the closure of the heart valves depends not on a static back pressure nor upon eddies but is primarily the consequence of the decelerated systolic efflux. This pioneer research of Ceradini was first published in German in 1872 ( 4 ). The purpose of the present report is to revisit Ceradini's pioneering experiments and his interpretation of heart valve closure, which remains as true as it was in 1872.

2007 ◽  
Vol 362 (1484) ◽  
pp. 1437-1443 ◽  
Author(s):  
Adrian H Chester ◽  
Patricia M Taylor

The cells that reside within valve cusps play an integral role in the durability and function of heart valves. There are principally two types of cells found in cusp tissue: the endothelial cells that cover the surface of the cusps and the interstitial cells (ICs) that form a network within the extracellular matrix (ECM) within the body of the cusp. Both cell types exhibit unique functions that are unlike those of other endothelial and ICs found throughout the body. The valve ICs express a complex pattern of cell-surface, cytoskeletal and muscle proteins. They are able to bind to, and communicate with, each other and the ECM. The endothelial cells on the outflow and inflow surfaces of the valve differ from one another. Their individual characteristics and functions reflect the fact that they are exposed to separate patterns of flow and pressure. In addition to providing a structural role in the valve, it is now known that the biological function of valve cells is important in maintaining the integrity of the cusps and the optimum function of the valve. In response to inappropriate stimuli, valve interstitial and endothelial cells may also participate in processes that lead to valve degeneration and calcification. Understanding the complex biology of valve interstitial and endothelial cells is an important requirement in elucidating the mechanisms that regulate valve function in health and disease, as well as setting a benchmark for the function of cells that may be used to tissue engineer a heart valve.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Dejia Liu ◽  
Sükrü Caliskan ◽  
Bita Rashidfarokhi ◽  
Harriëtte Oldenhof ◽  
Klaus Jung ◽  
...  

AbstractFreeze-drying can be used to ensure off-the-shelf availability of decellularized heart valves for cardiovascular surgery. In this study, decellularized porcine aortic heart valves were analyzed by nitroblue tetrazolium (NBT) staining and Fourier transform infrared spectroscopy (FTIR) to identify oxidative damage during freeze-drying and subsequent storage as well as after treatment with H2O2 and FeCl3. NBT staining revealed that sucrose at a concentration of at least 40% (w/v) is needed to prevent oxidative damage during freeze-drying. Dried specimens that were stored at 4 °C depict little to no oxidative damage during storage for up to 2 months. FTIR analysis shows that fresh control, freeze-dried and stored heart valve specimens cannot be distinguished from one another, whereas H2O2- and FeCl3-treated samples could be distinguished in some tissue section. A feed forward artificial neural network model could accurately classify H2O2 and FeCl3 treated samples. However, fresh control, freeze-dried and stored samples could not be distinguished from one another, which implies that these groups are very similar in terms of their biomolecular fingerprints. Taken together, we conclude that sucrose can minimize oxidative damage caused by freeze-drying, and that subsequent dried storage has little effects on the overall biochemical composition of heart valve scaffolds.


2021 ◽  
Vol 129 (Suppl_1) ◽  
Author(s):  
YenChun Ho ◽  
Xin Geng ◽  
Rohan Varshney ◽  
Jang Kim ◽  
Sandeep Surbrahmanian ◽  
...  

Background: Heart valves regulate the unidirectional forward flow and prevent retrograde backflow of blood during the cardiac cycle. Cardiac valve disease (CVD) is observed in approximately 2.5% of the general population and the incidence increases to ~10% in elderly people. Patients with severe CVD require surgery and effective pharmacological treatments are currently not available. PROX1 is a transcription factor that regulates the development of lymphatic, venous, and lymphovenous valves (vascular valves). We identified that PROX1 is also expressed in a subset of valvular endothelial cells (VECs) that are located on the downstream (fibrosa) side of cardiac valves. Whether PROX1 regulates cardiac valve development and disease is not known. Method and Results: We have discovered that mice lacking Prox1 in their VECs ( Prox1 ΔVEC ) develop enlarged aortic and mitral valves in which the expression of proteoglycans is increased (control, N=10; Prox1 ΔVEC , N=9, p <0.05). Echocardiography revealed moderate to severe stenosis of aortic valves of Prox1 ΔVEC mice (control, N=5; Prox1 ΔVEC , N=9, p <0.05). PROX1 regulates the expression of the transcription factor FOXC2 in the vascular valves. Similarly, we have found that the expression of FOXC2 is downregulated in the VECs of Prox1 ΔVEC mice. Specific knockdown of FOXC2 in VECs results in the thickening of aortic valves (control, N=10; shFoxc2 ΔVEC , N=8, p <0.05). Furthermore, restoration of FOXC2 expression in VECs ( Foxc2 OE-VEC ) ameliorates the thickening of the aortic valves of Prox1 ΔVEC mice ( Prox1 ΔVEC , N=9; Foxc2 OE-VEC ; Prox1 ΔVEC , N=8, p <0.05). We have also determined that the expression of platelet-derived growth factor-B ( Pdgfb ) is increased in the valve tissue of Prox1 ΔVEC mice and in PROX1 deficient sheep mitral valve VECs (MVECs) (siCtrl , N=4; siProx1 , N=4, p <0.05). Additionally, hyperactivation of PDGF-B signaling in mice results in a phenotype that is similar to Prox1 ΔVEC mice (control , N=4; Pdgfb GOF , N=3, p <0.05). Conclusion: Together these data suggest that PROX1 maintains the extracellular matrix composition of cardiac valves by regulating the expressions of FOXC2 and PDGF-B in VECs.


2021 ◽  
Author(s):  
Mengyue Hu ◽  
Xu Peng ◽  
Yang Zhao ◽  
Xiaoshuang Yu ◽  
Can Cheng ◽  
...  

To conveniently and effectively cure heart valve diseases or defects, combining with transcatheter valve technology, bioprosthetic heart valves (BHVs) originated from the decellularized porcine pericardium (D-PP) have been broadly used...


2011 ◽  
Vol 2011 ◽  
pp. 1-13 ◽  
Author(s):  
Gretchen J. Mahler ◽  
Jonathan T. Butcher

Heart valve disease is unique in that it affects both the very young and very old, and does not discriminate by financial affluence, social stratus, or global location. Research over the past decade has transformed our understanding of heart valve cell biology, yet still more remains unclear regarding how these cells respond and adapt to their local microenvironment. Recent studies have identified inflammatory signaling at nearly every point in the life cycle of heart valves, yet its role at each stage is unclear. While the vast majority of evidence points to inflammation as mediating pathological valve remodeling and eventual destruction, some studies suggest inflammation may provide key signals guiding transient adaptive remodeling. Though the mechanisms are far from clear, inflammatory signaling may be a previously unrecognized ally in the quest for controlled rapid tissue remodeling, a key requirement for regenerative medicine approaches for heart valve disease. This paper summarizes the current state of knowledge regarding inflammatory mediation of heart valve remodeling and suggests key questions moving forward.


2009 ◽  
Vol 42 (12) ◽  
pp. 1804-1824 ◽  
Author(s):  
Michael S. Sacks ◽  
W. David Merryman ◽  
David E. Schmidt
Keyword(s):  

2021 ◽  
Vol 73 (7) ◽  
pp. 478-484
Author(s):  
Watcharit Anantakal ◽  
◽  
Somboon Thamtakerngkit ◽  
Vijarn Vachirawongsakorn ◽  
◽  
...  

Objective: To compare the heart valve circumference before and after 10% formalin fixation. Materials and Methods: The study analyzed 63 Thai human cadaveric hearts. Each heart valve circumference was separately measured in the fresh state by specifically designed equipment. After that, the hearts were fixed in 10% formalin for 3 days. Then each heart valve circumference was measured by the same equipment and by the thread and ruler technique. The results were analyzed using SPSS package to find the association between the heart valve circumference before and after formalin fixation. Results: This study showed that the average circumferences of the heart valve measured in the fresh state were 13.329 cm in the tricuspid valve, 10.617 cm in the mitral valve, 8.416 cm in the pulmonic valve, and 7.122 cm in the aortic valve. The average circumferences of the heart valve measured after 10% formalin fixation were 11.019 cm in the tricuspid valve, 8.714 cm in the mitral valve, 6.751 cm in the pulmonic valve, and 6.089 cm in the aortic valve. The average ratios of the heart valve circumference measured fresh and after 10% formalin fixation were 0.8267 in the tricuspid valve, 0.8235 in the mitral valve, 0.8050 in the pulmonic valve, and 0.8573 in the aortic valve. There were significant differences in the heart valve circumference between the fresh state and after formalin fixation (p < 0.001). Conclusion: This study revealed important information on the dimensional changes of all the formalin-fixed heart valves. We found that the heart valve shrank after formalin fixation, with the formalin-fixed hearts an estimated 0.8 times smaller than the fresh cadaveric hearts.


2021 ◽  
Vol 25 (3) ◽  
pp. 106
Author(s):  
R. N. Komarov ◽  
A. O. Simonyan ◽  
I. A. Borisov ◽  
V. V. Dalinin ◽  
A. M. Ismailbaev ◽  
...  

<p>Various types of autologous materials are used in heart valve surgery, particularly the aortic valve, and this article describes their historical development. The evolution of the use of various autogenous tissues, such as the aortic wall, fascia lata of the thigh, pericardium and others is described and discussed in detail. This paper presents the results of experimental and clinical publications devoted to the surgical techniques and the outcomes of heart valve reconstruction using such materials. The negative aspects of the use of a wide range of autografts are discussed, including the short service life and low strength, which led to declining interest in this group of reconstructive interventions. The method for treating the autopericardium with glutaraldehyde, proposed in 1986 by C.S. Love, J.W. Love and colleagues, raised the use of autologous materials in the reconstruction of heart valves to a new level, allowing surgeons to strengthen the autopericardial flaps and increase resistance to hemodynamic stress. Many surgeons, their interest in such treatment methods increased by this discovery, then reported their observations and further developed ways of using the treated autopericardium in aortic valve surgery. Particularly, the method of neocuspidisation of the aortic valve, introduced into wide practice by M.G. Duran and S. Ozaki, has become the quintessential reconstructive valve surgery involving the use of autologous materials.</p><p>Received 14 March 2021. Revised 26 April 2021. Accepted 27 April 2021.</p><p><strong>Funding:</strong> The study did not have sponsorship.</p><p><strong>Conflict of interest:</strong> The authors declare no conflicts of interests.</p><p><strong>Contribution of the authors</strong><br />Conception and study design: A.O. Simonyan, A.M. Ismailbaev<br />Drafting the article: A.O. Simonyan, A.M. Ismailbaev, N.O. Kurasov, M.I. Tcheglov<br />Critical revision of the article: R.N. Komarov, V.V. Dalinin, I.A. Borisov<br />Final approval of the version to be published: R.N. Komarov, A.O. Simonyan, I.A. Borisov, V.V. Dalinin, A.M. Ismailbaev, N.O. Kurasov, M.I. Tcheglov</p>


Author(s):  
NN Subhash ◽  
Adathala Rajeev ◽  
Sreedharan Sujesh ◽  
CV Muraleedharan

Average age group of heart valve replacement in India and most of the Third World countries is below 30 years. Hence, the valve for such patients need to be designed to have a service life of 50 years or more which corresponds to 2000 million cycles of operation. The purpose of this study was to assess the structural performance of the TTK Chitra tilting disc heart valve model TC2 and thereby address its durability. The TC2 model tilting disc heart valves were assessed to evaluate the risks connected with potential structural failure modes. To be more specific, the studies covered the finite element analysis–based fatigue life prediction and accelerated durability testing of the tilting disc heart valves for nine different valve sizes. First, finite element analysis–based fatigue life prediction showed that all nine valve sizes were in the infinite life region. Second, accelerated durability test showed that all nine valve sizes remained functional for 400 million cycles under experimental conditions. The study ensures the continued function of TC2 model tilting disc heart valves over duration in excess of 50 years. The results imply that the TC2 model valve designs are structurally safe, reliable and durable.


2018 ◽  
Vol 5 (3) ◽  
pp. 74 ◽  
Author(s):  
Fardin Khalili ◽  
Peshala Gamage ◽  
Richard Sandler ◽  
Hansen Mansy

Artificial heart valves may dysfunction, leading to thrombus and/or pannus formations. Computational fluid dynamics is a promising tool for improved understanding of heart valve hemodynamics that quantify detailed flow velocities and turbulent stresses to complement Doppler measurements. This combined information can assist in choosing optimal prosthesis for individual patients, aiding in the development of improved valve designs, and illuminating subtle changes to help guide more timely early intervention of valve dysfunction. In this computational study, flow characteristics around a bileaflet mechanical heart valve were investigated. The study focused on the hemodynamic effects of leaflet immobility, specifically, where one leaflet does not fully open. Results showed that leaflet immobility increased the principal turbulent stresses (up to 400%), and increased forces and moments on both leaflets (up to 600% and 4000%, respectively). These unfavorable conditions elevate the risk of blood cell damage and platelet activation, which are known to cascade to more severe leaflet dysfunction. Leaflet immobility appeared to cause maximal velocity within the lateral orifices. This points to the possible importance of measuring maximal velocity at the lateral orifices by Doppler ultrasound (in addition to the central orifice, which is current practice) to determine accurate pressure gradients as markers of valve dysfunction.


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