scholarly journals The morphometric measurements of the gross structural changes of mitral valve in valvular stenosis with or without regurgitation

2015 ◽  
Vol 9 (1) ◽  
pp. 7-11
Author(s):  
Golam Mohammad Kibria
Keyword(s):  
Mitral Valve ◽  
Adult Male ◽  
Structural Changes ◽  
Effective Orifice Area ◽  
Chordae Tendineae ◽  
Morphometric Measurements ◽  
Mitral Valves ◽  
Replacement Surgery ◽  
Valvular Stenosis ◽  
Normal Mitral Valve

Rheumatic mitral stenosis is still a cardiac problem in developing countries. Reconstructive and replacement surgery of the diseased valves are often needed. Most of the studies on stenotic mitral valves are echocardiographic one. Morphometric measurements of the stenotic mitral valve and comparison with that in the normal mitral valve is done in this study. Thirty seven hearts of normal adult-male unclaimed dead-bodies from the mortuary of Forensic Medicine, Dhaka Medical College, Dhaka; and twelve surgically excised stenotic mitral valves of the adult-male cardiac patients from the National Institute of Cardiovascular Diseases, Dhaka, Bangladesh were studied in fresh condition. The detail morphometric findings were compared between two groups. Though the total annular circumference was similar in both groups, yet the effective orifice area reduced significantly in stenotic valves. The anterior leaflet-area was increased, but the posterior leaflet-area was decreased in the stenotic valves. The thickness of the stenotic leaflets and chordae tendineae were increased compared to that in normal valves. The knowledge of the pathological changes of the valves would help to understand the exact pathophysiological mechanisms involved in the cardiac valve diseases.Faridpur Med. Coll. J. 2014;9(1): 7-11

Hemodynamics of the Mitral Valve Under Edge-to-Edge Repair: An In Vitro Steady Flow Study

2009 ◽  
Vol 131 (5) ◽  
Author(s):  
Liang Shi ◽  
Zhaoming He
Keyword(s):  
Mitral Valve ◽  
Left Ventricle ◽  
Position Effect ◽  
Maximum Velocity ◽  
Central Position ◽  
Effective Orifice Area ◽  
Orifice Area ◽  
Mitral Valves ◽  
Repair Technique ◽  
Normal Mitral Valve

Edge-to-edge repair (ETER) is a mitral valve repair technique that restores valvular competence by suturing together the free edges of two leaflets. This repair technique alters mitral valve inflow and thus left ventricle hemodynamics during diastole. Our objective was to investigate fluid mechanics immediately downstream of the mitral valve under ETER during diastole. Fresh porcine mitral valves of the annulus size M32 with chordae removed were installed into a steady flow loop simulating a peak diastolic inflow through the mitral valve. Digital particle image velocimetry was used to measure the velocity field immediately downstream of the mitral valve under normal and ETER conditions. First, to study the suture length effect, suture was applied in the central position of the leaflet edge with suture lengths of 3 mm, 6 mm, and 9 mm, respectively. Then, 3 mm suture was set in the central, lateral, and commissural positions of the leaflet edge to study the suture position effect. Flow rate was 15 l/min. Velocity, Reynolds shear stress (RSS), and effective orifice area were assessed. A total of five mitral valves were tested. The normal mitral valve without the ETER had one jet downstream of the valve, but the mitral valve with the central or lateral sutures under the ETER had two jets downstream of the valve with a recirculation region downstream of the suture. The maximum velocity, the maximum RSS in the jets, the pressure drop across the mitral valve, and the jet deflection angle increased with the increase in suture length in the central position. When the suture position effect was investigated with the 3 mm suture, the maximum velocity, the maximum RSS, and the pressure drop across the valve in the central suture position were greater than those of the lateral and the commissural suture positions. The lateral suture demonstrated major and minor jets with the greater maximum velocity and maximum RSS in the major jet. When the suture was in the commissural position, the flow field downstream of the mitral valve was similar to that of the normal mitral valve without the ETER. The effective orifice area was smallest when the suture was applied in the central position as compared with other suture positions. Both suture length and position have an important impact on fluid mechanics downstream of the mitral valve under the ETER in terms of flow pattern, maximum velocity, and RSS distribution. The altered hemodynamics of the mitral valve and thus of the left ventricle by the ETER may change mitral valve and left ventricle function.

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].

Republished: A case of right middle cerebral artery ‘tendonectomy’ following mitral valve replacement surgery

2017 ◽  
Vol 9 (9) ◽  
pp. e35-e35 ◽  
Author(s):  
Mary C Thomas ◽  
Josser E Delgado Almandoz ◽  
Adam J Todd ◽  
Mark L Young ◽  
Jennifer L Fease ◽  
...  
Keyword(s):  
Mitral Valve ◽  
Middle Cerebral Artery ◽  
Valve Replacement ◽  
Mitral Valve Replacement ◽  
Cerebral Artery ◽  
Mechanical Thrombectomy ◽  
Chordae Tendineae ◽  
Replacement Surgery ◽  
The Right ◽  
Valve Replacement Surgery

Following mechanical mitral valve replacement surgery, a 69-year-old woman had an ischemic stroke in the right middle cerebral artery territory. Mechanical thrombectomy showed the embolus to be a piece of chordae tendineae excised during the valve replacement surgery.

scholarly journals Interactive editing of virtual chordae tendineae for the simulation of the mitral valve in a decision support system

2020 ◽  
Author(s):  
Lars Walczak ◽  
Lennart Tautz ◽  
Mathias Neugebauer ◽  
Joachim Georgii ◽  
Isaac Wamala ◽  
...  
Keyword(s):  
Decision Support ◽  
Mitral Valve ◽  
Decision Support System ◽  
Support System ◽  
Heuristic Method ◽  
Mitral Valve Surgery ◽  
Chordae Tendineae ◽  
Mitral Valves ◽  
Interactive Editing ◽  
Opening And Closing

Abstract Purpose Decision support systems for mitral valve disease are an important step toward personalized surgery planning. A simulation of the mitral valve apparatus is required for decision support. Building a model of the chordae tendineae is an essential component of a mitral valve simulation. Due to image quality and artifacts, the chordae tendineae cannot be reliably detected in medical imaging. Methods Using the position-based dynamics framework, we are able to realistically simulate the opening and closing of the mitral valve. Here, we present a heuristic method for building an initial chordae model needed for a successful simulation. In addition to the heuristic, we present an interactive editor to refine the chordae model and to further improve pathology reproduction as well as geometric approximation of the closed valve. Results For evaluation, five mitral valves were reconstructed based on image sequences of patients scheduled for mitral valve surgery. We evaluated the approximation of the closed valves using either just the heuristic chordae model or a manually refined model. Using the manually refined models, prolapse was correctly reproduced in four of the five cases compared to two of the five cases when using the heuristic. In addition, using the editor improved the approximation in four cases. Conclusions Our approach is suitable to create realistically parameterized mitral valve apparatus reconstructions for the simulation of normally and abnormally closing valves in a decision support system.

Total Reconstruction of the Mitral Valve with Autopericardium: Anatomical Study

2002 ◽  
Vol 10 (2) ◽  
pp. 137-140
Author(s):  
Vahe C Gasparyan ◽  
Van S Galstyan
Keyword(s):  
Mitral Valve ◽  
Valve Replacement ◽  
Prosthetic Valve ◽  
Anatomical Study ◽  
Good Alternative ◽  
Native Valve ◽  
Mitral Valves ◽  
Autologous Pericardium ◽  
Total Reconstruction ◽  
Normal Mitral Valve

Mitral valve repair has several advantages over prosthetic valve replacement. A new technique of total reconstruction of the mitral valve with autologous pericardium is described. The native mitral valve leaflets and chordae were excised from 10 human cadaver hearts, in the same way as for prosthetic valve replacement. The dimensions of the physiologically normal mitral valve were used to calculate the parameters for tailoring a corresponding new valve. Autologous pericardium was fixed in 0.625% glutaraldehyde solution for 10 minutes. The calculated parameters of the mitral valve were marked on the pericardium. The new valve was fashioned and inserted in the native valve position. Hydraulic probes showed good competence in all 10 reconstructed mitral valves. This method might be a good alternative to prosthetic valve replacement.

scholarly journals The role of strut chordae in mitral valve competence during annular dilation

Perfusion ◽  
2020 ◽  
pp. 026765912094134
Author(s):  
Samuel Taylor ◽  
Keith G Buchan ◽  
Daniel M Espino
Keyword(s):  
Mitral Valve ◽  
Systolic Pressure ◽  
Mitral Annulus ◽  
Chordae Tendineae ◽  
Mitral Valves ◽  
Significant Difference ◽  
Normal Configuration ◽  
Annular Dilation

Strut chordae, on their own, are not typically thought to aid mitral valve competence. The aim of this study is to assess whether strut chordae aid mitral valve competence during acute annular dilation. Twelve porcine hearts were dissected and tested using an in vitro simulator, with the mitral annulus tested in either a ‘normal’ or a dilated configuration. The normal configuration included a diameter of 30 mm, a posterior leaflet ‘radius’ of 15 mm and a commissural corner ‘radius’ of 7.5 mm; the dilated annular template instead used dimensions of 50 mm, 25 mm and 12.5 mm, respectively. Each mitral valve underwent ten repeat tests with a target systolic pressure of 100 mmHg. No significant difference in the pressure was detected between the dilated and regular annuli for the mitral valves tested (95 ± 3 mmHg cf. 95 ± 2 mmHg). However, the volume of regurgitation for a dilated annulus was 28 ml greater than for a valve with a normal annulus. Following severing of strut chordae, there was a significant reduction in the systolic pressure withstood before regurgitation by mitral valves with dilated annuli (60 ± 29 mmHg cf. 95 ± 2 mmHg for normal annular dimensions; p < 0.05). In conclusion, strut chordae tendineae may play a role in aiding mitral valve competence during pathophysiology.

scholarly journals Histological features of the mitral valve in normal and opioid exposure in experiment

2019 ◽  
Vol 25 (3) ◽  
pp. 40-44
Author(s):  
L.R. Mateshuk-Vatseba ◽  
R.R. Symivska ◽  
N.V. Belik ◽  
V.V. Piliponova
Keyword(s):  
Endothelial Cells ◽  
Mitral Valve ◽  
Elastic Layer ◽  
Morphological Changes ◽  
Reproductive Age ◽  
Elastic Fibers ◽  
Destructive Effect ◽  
Mitral Valves ◽  
Normal Mitral Valve ◽  
Smooth Myocytes

To date, pathology of the cardiovascular system is the most common, tends to increase, most often leads to disability and mortality of the population at a young working age and is an important medical and social problem. The purpose of the study was to establish the features of micro organization of the mitral valve in white rat in norm and after opioid action. The study material is presented by histological samples of a mitral valve of the white rat. The study was performed on 30 adult white reproductive age rats weighing 160-220 g. The experimental animals were injected intramuscularly 1 time per day for the same period of 42 days (6 weeks) with the opioid drug analgesic “Nalbuphine”. Using histological methods, 30 mitral valves of white rat were examined. Microscopy of histological preparations of the valves of the heart was performed sequentially, assessing the morphological changes in the norm and under the action of the opioid after 6 weeks of the experiment. Emphasis was placed on the presence or absence of endothelial layer, as well as the condition of endothelial cells in normal and at the action of the damaging factor, determining the signs of their dystrophy, desquamation and proliferation. It is established that the normal mitral valve is represented by endocardial folds. The rat endocardium consists of three layers: endothelial (endothelial cells rich layer, attached to the basement membrane), subendothelial (connective tissue rich in fibroblasts) and a muscular-elastic layer (represented by smooth myocytes, plaited collagen fibers). After 6 weeks of administration of Nalbuphine, the mitral valve is in a stage of decompensation, when the outer and inner endothelial layers are destroyed, the endothelial cells are deformed, the subendothelial layer is represented by single bundles of different directions. In the musculo-elastic layer, contact between smooth myocytes and fragmented and thinned, collagen and elastic fibers is lost. This study allows us to conclude on the destructive effect of opioid agents on the valvular apparatus of the heart.

P1782Synchrotron-based 4D-X-ray Phase Tomography of fresh chordae tendineae of mitral valve

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
T Tsukube ◽  
K Yokawa ◽  
Y Okita ◽  
K Ataka ◽  
M Hoshino ◽  
...  
Keyword(s):  
Mitral Valve ◽  
Cross Section ◽  
Structural Changes ◽  
Soft Tissues ◽  
Mechanical Load ◽  
Frame Rate ◽  
Chordae Tendineae ◽  
Tomographic Images ◽  
X Ray ◽  
Dimensional Changes

Abstract Background Mechanical properties of chordae tendineae of mitral valve (MV) are still not fully investigated. Synchrotron-based X-ray phase tomography (XPCT) is a powerful tool to measure biological soft tissues. Recently, we have developed dynamic X-ray phase tomography (4D-XPCT) to discuss the dynamic phenomena of biological samples quantitatively and applied to chordae tendineae of MV (MVCT). Purpose This study evaluated 4-dimensional changes of MVCT and clarified structural changes of MVCT during cardiac cycles. Methods The X-ray energy for 4D XPCT was set to 20keV. The effective pixel size was 7.8μm. Fresh MVCT extracted from a pig heart were measured in the specially designed container filled with normal cold saline. MVCT installed on the sample stage was stretched and released with a continuous oscillation of 0.5Hz during a phase tomographic measurement. The amount of stretch was 400μm where a mechanical load caused by stretching was approximately 1N. In this measurement, projection images were acquired with a frame rate of 20Hz during a single sawtooth wave. Therefore, apparent frame rate of 20Hz is expected in 4D phase tomography. Cross section was determined by simple thresholding based on the density. In this case, the threshold was set to 1.018g/cm3. Results X-ray phase tomographic images of MVCT at the released (A) and stretched (B) conditions are shown in Fig. 1a. The load applied to the sample and change of the cross section obtained from tomography during stretching and releasing are shown in Fig. 1b and 1c, respectively. The diameter of chordae tendinea were changed approximately 2.5% during stretching and returned to initial diameter during releasing. Figure 1 Conclusions This result demonstrated that the 4D-XPCT had a capability to trace the detail of deformation process in the biological soft tissues during continuous oscillation. Even chordae tendinea are mainly consisted of collagen fibers, diameter of the chordae was changed according to stretching and releasing.

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