Abstract 14888: Extracellular Matrix Quantification of Fully Regenerated Neochorade After Bio-scaffold Mitral Valve Implantation in a Juvenile Non-human Primate Model

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Brittany A Gonzalez ◽  
Marcos Gonzalez Perez ◽  
Asad Mirza ◽  
Frank Scholl ◽  
Steven Bibevski ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Mitral Valve ◽  
Oscillatory Flow ◽  
Treatment Options ◽  
Left Ventricular ◽  
Primate Model ◽  
Cardiac Tissues ◽  
Mitral Valves ◽  
Intestinal Submucosa ◽  
Post Implantation

Introduction: To investigate enhanced treatment options for critical mitral valve disease in children, we implanted a bio-scaffold mitral valve comprising of porcine small intestinal submucosa (PSIS) in a juvenile baboon model. Hypothesis: New tissue formation would be accelerated at physical connections between the replacement bio-scaffold valve and native cardiac tissues, due to direct extracellular matrix (ECM) communications. Methods: Juvenile baboons (n=2) were implanted with a hand-made bicuspid PSIS (Cormatrix, Roswell, GA) mitral valve. The PSIS valves were excised at 11- and 20-months post-implantation. Images of histological stains (Movat’s Pentachrome; Alizée Pathology, Inc., Thurmont, MD) were subsequently spatially mapped for ECM quantification (MATLAB; Mathworks, Natick, MA). Results: PSIS bio-scaffold mitral valves (11- and 20-months post-implantation) facilitated complete regeneration of neochordae. The neochordae seamlessly integrated into the papillary muscles and left ventricular insertion sites ( Figure 1A, E ). We also found that with an increase in implantation duration of ~ 9 months, the collagen, proteoglycan and elastin content (per mm 2 ; Figure 1B-D, F-H ) had a fold-change of 6.96, 18.42 and 4.94, respectively. Conclusions: Our findings suggest that the PSIS bio-scaffold mitral valve apparatus can regenerate neochordae without the need for any biochemical or biomechanical treatment. Nonetheless, other valve spatial areas of importance (e.g. leaflets) will require additional strategies. As a next step, we will produce oscillatory flow-conditioned, stem cell-derived ECM, to accelerate tissue regeneration. The mechanical parameters that we computed to permit physiological oscillatory flow conditions are an oscillatory shear index (OSI) of 0.23 and time averaged bio-scaffold shear stress (TAB-SSS) of 4.6 dynes/cm 2 . Acknowledgements: AHA Award ID: 16GRNT31090009; The Miami Research Heart Institute; FIU-UGS DYF.

Functional Evaluation of the Medtronic Stentless Porcine Xenograft Mitral Valve in Sheep

Circulation ◽  
1999 ◽  
Vol 100 (suppl_2) ◽  
Author(s):  
Paul Dagum ◽  
G. Randall Green ◽  
Tomasz A. Timek ◽  
George T. Daughters ◽  
Linda E. Foppiano ◽  
...  
Keyword(s):  
Mitral Valve ◽  
Lateral Displacement ◽  
Left Ventricular Pressure ◽  
Left Ventricular ◽  
Control Group ◽  
Attractive Alternative ◽  
Functional Evaluation ◽  
Mitral Valves ◽  
Hemodynamic Performance ◽  
Porcine Xenograft

Background —Recently, renewed interest in allograft and stentless “freehand” bileaflet xenograft mitral valve replacement has arisen. The variability of human papillary tip anatomy and scarcity of donors limit allograft availability, making xenograft mitral valves an attractive alternative; however, these valves require new surgical implantation techniques, and assessment of their hemodynamics and functional geometry is lacking. Methods —Seven sheep underwent implantation of a new stentless, glutaraldehyde-preserved porcine mitral valve (Physiological Mitral Valve [PMV], Medtronic) and were studied acutely under open-chest conditions. A new method of retrograde cardioplegia was developed. Hemodynamic valve function was assessed by epicardial Doppler echocardiography. 3D motion of miniature radiopaque markers sutured to the valve leaflets, annulus, and papillary tips was measured. Six other sheep with implanted markers served as controls. Results —Both papillary muscle tips avulsed in the first animal, leaving 6 other animals. Mitral regurgitation was not observed in any xenograft valve. The peak and mean transvalvular gradients were 4.6±1.8 mm Hg and 2.6±1.5 mm Hg, respectively. The average mitral valve area was 5.7±1.6 cm 2 . Valve closure in the xenograft group occurred later (30±11 ms, P <0.015) and at higher left-ventricular pressure (61±9 mm Hg, P <0.001) than in the control group; furthermore, leaflet coaptation was displaced more apically (5.6±2.2 mm, P <0.001) and septally (5.8±1.5 mm, P <0.001), and the anterolateral papillary tip underwent greater septal-lateral displacement (2.7±1.5 mm, P <0.001). Annular contraction during the cardiac cycle was similar in the 2 groups (xenograft 9.2±4.5% versus control 10.6±4.5% [mean±SD; 2-factor ANOVA model]). Conclusions —Successful freehand stentless porcine mitral valve implantation is feasible in sheep and was associated with excellent early postoperative hemodynamics. Physiological mitral valve annular contraction and functional leaflet closure mechanics were preserved. Long-term valve durability, calcification, and hemodynamic performance remain to be determined in models.

Coaptation Mechanism of Dilated Mitral Valves

2010 ◽  
Author(s):  
Bo Gao ◽  
Zhaoming He
Keyword(s):  
Mitral Valve ◽  
Mitral Regurgitation ◽  
Left Ventricular Dysfunction ◽  
Ventricular Dysfunction ◽  
Left Ventricular ◽  
Functional Mitral Regurgitation ◽  
Common Complication ◽  
Mitral Valves ◽  
Global Left Ventricular ◽  
Normal Mitral Valve

Functional mitral regurgitation, which occurs as a consequence of regional of global left ventricular or global left ventricular dysfunction despite structurally normal mitral valve (MV), is a common complication in patients with ischemic or non-ischemic cardiomyopathies [1].

scholarly journals Case of trileaflet mitral valve: an important differential for non-classical intracavitary gradient in suspected hypertrophic cardiomyopathy

2019 ◽  
Vol 12 (6) ◽  
pp. e229106
Author(s):  
Joseph Barker ◽  
Neil Silverwood ◽  
Robert Gerber
Keyword(s):  
Hypertrophic Cardiomyopathy ◽  
Mitral Valve ◽  
Left Ventricular ◽  
Congenital Deformity ◽  
Disease Course ◽  
Posterior Leaflet ◽  
Exertional Dyspnoea ◽  
Mitral Valves ◽  
Left Ventricular Outflow ◽  
Very High

There are nine published reports of trileaflet mitral valves globally. As such their implication on health outcomes and associations with other disease is uncertain. This case describes a 62-year-old man presenting with exertional dyspnoea and hypertension. It describes an early misdiagnosis of hypertrophic cardiomyopathy and highlights that clinicians should be alerted in cases of very high left ventricular outflow gradients in the presence of eccentric mitral regurgitation (MR). Here the MR was caused by a rare congenital deformity whereby a deep cleft in the posterior leaflet resulted in a tricuspid appearance. We present the natural disease course of a trileaflet mitral valve and without intervention over 13 years from symptom onset to the development of severe MR.

scholarly journals Percutaneous Interventions for Secondary Mitral Regurgitation

2020 ◽  
Vol 13 (8) ◽  
Author(s):  
Mahboob Ali ◽  
Satya S. Shreenivas ◽  
David N. Pratt ◽  
Donald R. Lynch ◽  
Dean J. Kereiakes
Keyword(s):  
Clinical Trials ◽  
Mitral Valve ◽  
Mitral Regurgitation ◽  
Mitral Valve Repair ◽  
Treatment Options ◽  
Left Ventricular ◽  
Ventricular Assist Devices ◽  
Functional Mitral Regurgitation ◽  
Left Ventricular Assist Devices ◽  
Valve Repair

Mitral regurgitation is frequently associated with ventricular dysfunction and carries a high mortality. Guideline-directed medical therapy, surgical mitral valve repair or replacement, and, in the setting of advanced heart failure, heart transplant and left ventricular assist devices have been the mainstay of treatment. However, rapid advancement in the field has resulted in approval of edge-to-edge mitral valve repair with the MitraClip, and there are several novel catheter-based percutaneous options in clinical trials. Percutaneous options, while promising, must be deployed in patients who are most likely to benefit, and thus, understanding the pathophysiology of specific subgroups of patients with functional mitral regurgitation (eg, disproportionate versus proportionate mitral regurgitation) is key to the success of new devices. We review the pathophysiology, percutaneous therapeutic treatment options, and ongoing clinical trials for functional mitral regurgitation.

Effect of the αGal Epitope on the Response to Small Intestinal Submucosa Extracellular Matrix in a Nonhuman Primate Model

2009 ◽  
Vol 15 (12) ◽  
pp. 3877-3888 ◽  
Author(s):  
Kerry A. Daly ◽  
Ann M. Stewart-Akers ◽  
Hidetaka Hara ◽  
Mohamed Ezzelarab ◽  
Cassandra Long ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Nonhuman Primate ◽  
Small Intestinal Submucosa ◽  
Nonhuman Primate Model ◽  
Primate Model ◽  
Small Intestinal ◽  
Intestinal Submucosa

scholarly journals Flow structure in healthy and pathological left ventricles with natural and prosthetic mitral valves

2017 ◽  
Vol 834 ◽  
pp. 271-307 ◽  
Author(s):  
V. Meschini ◽  
M. D. de Tullio ◽  
G. Querzoli ◽  
R. Verzicco
Keyword(s):  
Mitral Valve ◽  
Ad Hoc ◽  
Stokes Equations ◽  
Mechanical Valve ◽  
Left Ventricular ◽  
Navier Stokes ◽  
Navier Stokes Equations ◽  
Mitral Valves ◽  
Bileaflet Mechanical Valve ◽  
Ventricle Volume

In this paper, the structure and the dynamics of the flow in the left heart ventricle are studied for different pumping efficiencies and mitral valve types (natural, biological and mechanical prosthetic). The problem is investigated by direct numerical simulation of the Navier–Stokes equations, two-way coupled with a structural solver for the ventricle and mitral valve dynamics. The whole solver is preliminarily validated by comparisons with ad hoc experiments. It is found that the system works in a highly synergistic way and the left ventricular flow is heavily affected by the specific type of mitral valve, with effects that are more pronounced for ventricles with reduced pumping efficiency. When the ventricle ejection fraction (ratio of the ejected fluid volume to maximum ventricle volume over the cycle) is within the physiological range (50 %–70 %), regardless of the mitral valve geometry, the mitral jet sweeps the inner ventricle surface up to the apex, thus preventing undesired flow stagnation. In contrast, for pathological ejection fractions (⩽40 %), the flow disturbances introduced by the bileaflet mechanical valve reduce the penetration capability of the mitral jet and weaken the recirculation in the ventricular apex. Although in clinical practice the fatality rates in the five-year follow-ups for mechanical and biological mitral valve replacements are essentially the same, a breakdown of the deaths shows that the causes are very different for the two classes of prostheses and the present findings are consistent with the clinical data. This might have important clinical implications for the choice of prosthetic device in patients needing mitral valve replacement.

scholarly journals Annular and subvalvular dynamics after extracellular matrix mitral tube graft implantation in pigs

2021 ◽  
Author(s):  
Marcell J Tjørnild ◽  
Lisa Carlson Hanse ◽  
Søren N Skov ◽  
Karen B Poulsen ◽  
Mona Sharghbin ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Mitral Valve ◽  
Mitral Annulus ◽  
Width Ratio ◽  
Potential Candidate ◽  
Mitral Valves ◽  
Mitral Valve Reconstruction ◽  
Regional Dynamics ◽  
The Impact ◽  
Graft Implantation

Abstract OBJECTIVES Entire mitral valve reconstruction with an extracellular matrix tube graft is a potential candidate to overcome the current limitations of mechanical and bioprosthetic valves. However, clinical data have raised concern with respect to patch failure. The aim of our study was to evaluate the impact of extracellular matrix mitral tube graft implantation on mitral annular and subvalvular regional dynamics in pigs. METHODS A modified tube graft design made of 2-ply extracellular matrix was used (CorMatrix®; Cardiovascular Inc., Alpharetta, GA, USA). The reconstructions were performed in an acute 80-kg porcine model (N = 8), where each pig acted as its own control. Haemodynamics were assessed with Mikro-Tip pressure catheters and mitral annular and subvalvular geometry and dynamics with sonomicrometry. RESULTS Catheter-based peak left atrial pressure and pressure difference across the mitral and aortic valves in the reconstructions were comparable to the values seen in the native mitral valves. Also comparable were maximum mitral annular area (755 ± 100 mm2), maximum septal-lateral distance (29.7 ± 1.7 mm), maximum commissure–commissure distance (35.0 ± 3.4 mm), end-systolic annular height-to-commissural width ratio (10.2 ± 1.0%) and end-diastolic interpapillary muscle distance (27.7 ± 3.3 mm). Systolic expansion of the mitral annulus was, however, observed after reconstruction. CONCLUSIONS The reconstructed mitral valves were fully functional without regurgitation, obstruction or stenosis. The reconstructed mitral annular and subvalvular geometry and subvalvular dynamics were found in the same range to those in the native mitral valve. A regional annular ballooning effect occurred that might predispose to patch failure. However, the greatest risk was found at the papillary muscle attachments.

scholarly journals Combined Aortic and Mitral Valve Stenosis in Mucopolysaccharidosis Syndrome Type I-S: A Report of a Rare Case

2021 ◽  
Author(s):  
Hakimeh Sadeghian ◽  
Afsaneh Sadeghian ◽  
Bahareh Eslami ◽  
Seyed Hesameddin Abbasi ◽  
Masoumeh Lotfi-Tokaldany
Keyword(s):  
Mitral Valve ◽  
Aortic Valve ◽  
Rare Case ◽  
Ventricular Hypertrophy ◽  
Left Ventricular ◽  
Mitral Valve Stenosis ◽  
Type I ◽  
Syndrome Type ◽  
Inherited Metabolic Disorder ◽  
Mitral Valves

Mucopolysaccharidosis (MPS) syndrome is an inherited metabolic disorder. In more than half of the patients with MPS syndrome, heart valve involvement is reported; however, combined aortic and mitral valve stenosis in MPS syndrome type I-S is very rare. We describe a 39-year-old man with severe mitral and aortic valve stenosis due to MPS syndrome type I-S. Transthoracic and transesophageal echocardiography revealed severe thickening and calcification in the aortic and mitral valves with severe left ventricular hypertrophy. The coronary arteries were normal in angiography.  

scholarly journals Successful Left Ventricular Assist Device Support in Patient with Bjork-Shiley Mitral Valve Replacement

2015 ◽  
Author(s):  
Navin Rajagopalan ◽  
David C. Booth
Keyword(s):  
Mitral Valve ◽  
Valve Replacement ◽  
Mitral Valve Replacement ◽  
Left Ventricular Assist Device ◽  
Ventricular Assist Device ◽  
Left Ventricular ◽  
Assist Device ◽  
Ventricular Assist ◽  
Mitral Valves ◽  
Left Ventricular Assist

There is limited clinical experience with left ventricular assist device therapy in patients with prosthetic mitral valves. We present a case of successful left ventricular assist device support in a patient with previous mechanical mitral valve replacement.

scholarly journals Mitral valve endocarditis caused by Pseudomonas aeruginosa: a case report

2014 ◽  
Vol 8 (05) ◽  
pp. 676-679 ◽  
Author(s):  
Marija Polovina ◽  
Tatjana Potpara ◽  
Ivana Milosevic ◽  
Jelena Stepanovic ◽  
Momcilo Jovanovic ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Mitral Valve ◽  
Ventricular Dysfunction ◽  
Clinical Presentation ◽  
Splenic Abscess ◽  
High Risk Patient ◽  
Good Prognosis ◽  
Left Ventricular ◽  
Mitral Valves ◽  
Artery Disease

Previously, endocarditis caused by Pseudomonas aeruginosa mostly involved right-sided valvular infection and generally carried a good prognosis. Recently, changes have been observed in the occurrence and clinical presentation of pseudomonal endocarditis, with increasing incidence of nosocomial infections and involvement of the aortic and mitral valves. Still, pseudomonal left-sided endocarditis is rare, but is frequently associated with complications and high mortality rates. A case of a high-risk patient with coronary artery disease and left-ventricular dysfunction, successfully treated for pseudomonal mitral valve endocarditis complicated by splenic abscess formation, is presented here.

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