scholarly journals Hemodynamic Performance of Dysfunctional Prosthetic Heart Valve with the Concomitant Presence of Subaortic Stenosis: In Silico Study

2020 ◽  
Vol 7 (3) ◽  
pp. 90
Author(s):  
Othman Smadi ◽  
Anas Abdelkarim ◽  
Samer Awad ◽  
Thakir D. Almomani
Keyword(s):  
Early Detection ◽  
Heart Valve ◽  
Heart Valves ◽  
Cfd Simulation ◽  
Treatment Plan ◽  
Mechanical Heart Valve ◽  
Prosthetic Heart Valve ◽  
Subaortic Stenosis ◽  
Prosthetic Heart Valves ◽  
The Impact

The prosthetic heart valve is vulnerable to dysfunction after surgery, thus a frequent assessment is required. Doppler electrocardiography and its quantitative parameters are commonly used to assess the performance of the prosthetic heart valves and provide detailed information on the interaction between the heart chambers and related prosthetic valves, allowing early detection of complications. However, in the case of the presence of subaortic stenosis, the accuracy of Doppler has not been fully investigated in previous studies and guidelines. Therefore, it is important to evaluate the accuracy of the parameters in such cases to get early detection, and a proper treatment plan for the patient, at the right time. In the current study, a CFD simulation was performed for the blood flow through a Bileaflet Mechanical Heart Valve (BMHV) with concomitant obstruction in the Left Ventricle Outflow Tract (LVOT). The current study explores the impact of the presence of the subaortic on flow patterns. It also investigates the accuracy of (BMHV) evaluation using Doppler parameters, as proposed in the American Society of Echocardiography (ASE) guidelines.

Simulations of the Hinge Flow Fields of a Bileaflet Mechanical Heart Valve Under Physiologic Pulsatile Aortic Conditions

2008 ◽  
Author(s):  
Hélène A. Simon ◽  
Liang Ge ◽  
Iman Borazjani ◽  
Fotis Sotiropoulos ◽  
Ajit P. Yoganathan
Keyword(s):  
Heart Valve ◽  
Heart Valves ◽  
Mechanical Heart Valve ◽  
Prosthetic Heart Valve ◽  
Prosthetic Heart Valves ◽  
Valve Design ◽  
Bileaflet Mechanical Heart Valve ◽  
Hinge Flow ◽  
Blood Elements

Native heart valves with limited functionality are commonly replaced by prosthetic heart valves. Since the first heart valve replacement in 1960, more than three million valves have been implanted worldwide. The most widely implanted prosthetic heart valve design is currently the bileaflet mechanical heart valve (BMHV), with more than 130,000 implants every year worldwide. However, studies have shown that this valve design can still cause major complications, including hemolysis, platelet activation, and thromboembolic events. Clinical reports and recent in vitro experiments suggest that these thrombogenic complications are associated with the hemodynamic stresses imposed on blood elements by the complex non-physiologic flow induced by the valve, in particular in the hinge region.

Simulations of Flow Through Bileaflet Mechanical Heart Valves With Asymmetric Leaflet Motion

2012 ◽  
Author(s):  
B. Min Yun ◽  
Lakshmi P. Dasi ◽  
Cyrus K. Aidun ◽  
Ajit P. Yoganathan
Keyword(s):  
Heart Valve ◽  
Heart Valves ◽  
Mechanical Heart Valve ◽  
Prosthetic Heart Valve ◽  
Prosthetic Heart Valves ◽  
Thromboembolic Events ◽  
Complex Flow ◽  
Blood Damage ◽  
Flow Through ◽  
Leaflet Motion

Prosthetic heart valves have been used for over 50 years to replace diseased native valves but still lead to severe complications such as platelet aggregation and thromboembolic events. The most widely implanted design is the bileaflet mechanical heart valve (BMHV). Most modern BMHV designs have better flow hemodynamics and blood damage performance than earlier-generation counterparts. However, blood element trauma and thromboembolic events still remain as major complications of current BMHV designs. These problems have been linked to blood damage caused by non-physiological stresses. These stresses are caused by the complex flow fields that arise due to prosthetic heart valve design. In order to reduce the severity of these complications, the blood damage that occurs in flows through prosthetic heart valves must be well understood.

Simulations of Flow Through Bileaflet Mechanical Heart Valves to Assess Platelet Damage

2011 ◽  
Author(s):  
B. Min Yun ◽  
Jingshu Wu ◽  
Cyrus K. Aidun ◽  
Ajit P. Yoganathan
Keyword(s):  
Heart Valve ◽  
Heart Valves ◽  
Mechanical Heart Valve ◽  
Prosthetic Heart Valve ◽  
Prosthetic Heart Valves ◽  
Thromboembolic Events ◽  
Complex Flow ◽  
Valve Design ◽  
Blood Damage ◽  
Flow Through

Prosthetic heart valves have been used for over 50 years to replace diseased native valves but still lead to severe complications such as hemolysis, platelet aggregation, and thromboembolic events. The most widely implanted design is the bileaflet mechanical heart valve (BMHV). Most modern BMHV designs have better flow hemodynamics and blood damage performance than their earlier-generation counterparts. However, blood element trauma and thromboembolic events still remain as major complications of current BMHV designs. These problems have been linked to blood element damage caused by non-physiological stresses. These stresses are caused by the complex flow fields that arise due to prosthetic heart valve design, particularly in the leaflet hinge region. In order to reduce the severity of these complications, the blood damage that occurs in flows through prosthetic heart valves must be well understood.

Modeling of Tissue Fatigue Damage in Bio-Prosthetic Heart Valve

2011 ◽  
Author(s):  
Caitlin Martin ◽  
Wei Sun
Keyword(s):  
Fatigue Damage ◽  
Heart Valve ◽  
Anticoagulant Therapy ◽  
Heart Valves ◽  
Prosthetic Heart Valve ◽  
Bovine Pericardium ◽  
Prosthetic Heart Valves ◽  
Mechanical Valves ◽  
In Vivo Degradation

Bio-prosthetic heart valves (BHVs) with leaflets made of glutaraldehyde-treated bovine pericardium (GLBP), have been used extensively to replace diseased heart valves. BHVs display superior hemodynamics to mechanical valves and eliminate the need for anticoagulant therapy; however, they exhibit poor durability resulting from in vivo degradation and fatigue damage of the leaflets.

TRIZ Based Tool Management Applied in Mechanical Heart Valve Engineering Systems

2012 ◽  
Vol 569 ◽  
pp. 521-524
Author(s):  
Feng Zhou ◽  
Yuan Yuan Cui ◽  
Liang Liang Wu ◽  
Yin Chen ◽  
Jie Yang ◽  
...  
Keyword(s):  
Heart Valve ◽  
Heart Valves ◽  
Production Systems ◽  
Mechanical Heart Valve ◽  
Complex Case ◽  
Evolutionary Development ◽  
Prosthetic Heart Valves ◽  
Engineering Systems ◽  
Device Structure

Artificial mechanical heart valve (MHV) replacement is the common cardiovascular surgical procedure, yet its effect is far from satisfaction. Most important reasons lie in the model design and choice of the materials in the fabrication of the prosthetic heart valves. Based on systematic design methodology of TRIZ theory (Russian acronym for Theory of Solving Inventive Problem), the device structure is analyzed by comparing the past successful designs generated during the evolution of MHV. This paper represents a modeling technique integrating the well-established TRIZ with the conflict and contradiction modeling, substance-field and product functional analysis tools and provides some important trends in evolutionary development of production systems in MHV design. By analyzing the structural behavior and material performance, a complex case study from the research of different structural patterns and characteristics of current tri-leaflet modeling shows the validity of TRIZ theory to guide MHV design.

scholarly journals Prophylaxis of thrombotic complications in a pregnant patients with prosthetic heart valves

2012 ◽  
Vol 61 (5) ◽  
pp. 10-24
Author(s):  
Aleksandr Davidovich Makatsariya ◽  
Viktoriya Omarovna Bitsadze ◽  
Dzhamilya Khizriyevna Khizroyeva ◽  
Vyacheslav Borisovich Nemirovskiy ◽  
Svetlana Vladimirovna Akinshina
Keyword(s):  
Heart Valve ◽  
Heart Valves ◽  
Anticoagulation Therapy ◽  
Mechanical Heart Valve ◽  
Prosthetic Heart Valves ◽  
Dose Selection ◽  
Heart Valve Prostheses ◽  
Adequate Dose ◽  
Thrombotic Complications ◽  
Valve Prostheses

In patients with prosthetic heart valves pregnancy and labor are associated with high risk. There are no established anticoagulation guidelines in pregnant women with mechanical heart valve prostheses. More often physiological hypercoagulable state during pregnancy can reveal acquired and/or inherited hemostasis abnormalities which were asymptotic before pregnancy. The presence in the history of patients the foetal loss syndrome, severe obstetric complications (severe preeclampsia, abruptio placenta, antenatal fetal death, feto-placental insufficiency), thrombosis events is an indication for the screening for genetic thrombophilia and antiphospholipid syndrome. The diagnosis of thrombophilia in patients with mechanical heart valve prostheses can explain the inefficiency of anticoagulation therapy, warfarin resistance, «floating» hemostasis markers and difficulties in adequate dose selection

Evaluation of Paravalvular Leakage in Novel Mechanical Heart Valve

2017 ◽  
Author(s):  
Ankit Saxena ◽  
Rohan Shad ◽  
Mrudang Mathur ◽  
Anwesha Chattoraj ◽  
Sujay Shad
Keyword(s):  
Heart Valve ◽  
Heart Valves ◽  
Cardiac Tissue ◽  
Mechanical Heart Valve ◽  
Prosthetic Heart Valve ◽  
3D Printed ◽  
Novel Method ◽  
Novel Devices ◽  
Careful Assessment ◽  
Unique Mechanism

We developed a new mechanical heart valve prototype with a unique mechanism for attachment to cardiac tissue. The development of novel prosthetic heart valve systems requires careful assessment of paravalvular leaks — leakage of fluid that takes place between the valve and the cardiac tissue it is attached to. Traditional methods of testing paravalvular leaks in flow chambers are not ideal for novel devices and may underestimate its true extent. In this paper we developed a novel method of quantifying paravalvular leaks involving the use of 3D printed prototype heart valves and cadaveric bovine hearts, and compared the results with those from commercially available Medtronic ATS mechanical bileaflet valves. The average leak in our final prototype heart valves were found to be 0.13 ml/sec, compared to 0.33 ml/sec in the ATS valve.

Research Contribution of Prosthetic Valve Manufacturers Interfacing Academic-Industry Research Efforts

1999 ◽  
Author(s):  
Xiao Gong ◽  
Yi-Ren Woo ◽  
Ajit P. Yoganathan ◽  
Andreas Anayiotos
Keyword(s):  
Heart Valve ◽  
Heart Valves ◽  
Clinical Performance ◽  
Thrombus Formation ◽  
Academic Research ◽  
Prosthetic Heart Valve ◽  
Structural Safety ◽  
Prosthetic Heart Valves ◽  
Implantable Medical Device ◽  
Valve Design

Abstract Prosthetic heart valve is one of the most successful implantable medical devices. However, introducing better performing and longer lasting prosthetic mechanical heart valves (MHV) into clinical use has been slow because predicting the long term performance of a new valve design is difficult. Although significant progresses in many scientific fronts relevant to prosthetic heart valve development have been achieved, we still have an imperfect understanding of host responses to an implantable medical device and incomplete knowledge in associating hemodynamic characteristics of a valve design to clinical performance. Valve designers, frequently need to over design the valve components to ensure structural safety and thus, sacrifice the opportunity to optimize performance. Complications such as infection, thrombus formation, thromboembolic incidents, and hemorrhage associated to the use of prosthetic valves are still reported and valve designers are working hard to eliminate them. Further advancing scientific knowledge in designing and evaluating prosthetic heart valves is of great interest to many Valve designers and manufacturers. Interfacing Industry and Academic research efforts has been thwarted due to predominantly proprietary issues. Considering the benefits of a better performing MHV to the patients, this industry session will bring researchers from various MHV companies and academic institutions to discuss how to share the results of scientific studies more effectively. This will help accelerate new MHV development without compromising the confidentiality of key valve design information. The issue of standardized MHV testing will also be addressed.

Impact of prosthetic heart valves on pregnancy in Bangladeshi women

Perfusion ◽  
2019 ◽  
Vol 34 (6) ◽  
pp. 446-452 ◽  
Author(s):  
Redoy Ranjan ◽  
Dipannita Adhikary ◽  
Sanjoy Kumar Saha ◽  
Sabita Mandal ◽  
Kamrul Hasan ◽  
...  
Keyword(s):  
Pregnancy Outcome ◽  
Heart Valve ◽  
Heart Valves ◽  
Prosthetic Heart Valve ◽  
Study Groups ◽  
Prosthetic Heart Valves ◽  
Group I ◽  
Mechanical Prostheses ◽  
Warfarin Embryopathy ◽  
Group Ii

Background: This study evaluated pregnancy outcome in women with a prosthetic heart valve, especially with the oral anticoagulation therapy that must be weighed against the risk of intracardiac thrombosis. Methods: This multicenter, retrospective, cohort study was undertaken between January 2012 and June 2017. The principal maternal outcome variables included bleeding and thromboembolic complications, infective endocarditis, prosthetic valve thrombosis and heart failure. However, the main foetal outcome variables included miscarriage, mortality, preterm baby, warfarin embryopathy, low birthweight and the mode of delivery. Results: A total of 265 pregnancies in women with prosthetic heart valves were evaluated in two groups: Group I (n = 182) covers a mechanical valve, while Group II (n = 82) covers a bioprosthetic valve. The mean age of the patients was 25.2 ± 2.5 years and 24.5 ± 5.2 years in Group I and Group II, respectively. Approximately 80% of the patients had normal echocardiography findings. However, Group I (mechanical prostheses) has a higher incidence (11.54%) of thrombus formation in comparison with the bioprostheses. Hemorrhagic complications and spontaneous miscarriage were statistically significant (p⩽0.05) between the study groups. However, normal pregnancy outcome (91.57%) was significantly higher (p⩽0.05) in Group II compared to Group I (61.54%). Mean birthweight and mean APGAR score were found normal in both study groups. Only 2.75% of patients have warfarin embryopathy in Group I. Furthermore, comparison of SF-36 scores for HRQOL (Health-Related Quality of Life) before and after pregnancy were statistically insignificant among the study population. Conclusion: Proper antenatal care and early risk stratification are the fundamental measures to improve the maternal and foetal outcomes in a patient with a prosthetic heart valve.

Pharmacogenetic testing in the management of patients with prosthetic heart valves

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
E.V Gorbunova ◽  
A.V Ponasenko ◽  
O.L Barbarash
Keyword(s):  
Heart Valve ◽  
Anticoagulant Therapy ◽  
Therapeutic Dose ◽  
Heart Valves ◽  
Warfarin Therapy ◽  
Mechanical Heart Valve ◽  
Early Postoperative Period ◽  
Prosthetic Heart Valves ◽  
Pharmacogenetic Testing ◽  
Polymorphic Variants

Abstract Background This study examined clinical, demographic, anthropometric, and inheritance factors that influence individual sensitivity to warfarin therapy after heart valve surgery. The clinical significance of the pharmacogenetic approach was assessed using the individual time frame and time spent in the INR therapeutic range. Purpose To study the influence of the preemptive panel-based pharmacogenetic testing on the effectiveness and safety of anticoagulant therapy in patients with prosthetic heart valves. Materials and methods The study included 928 patients (519 men and 409 female) (mean age 56±10 years) living in Western Siberia, Russia. Mainly there were patients with rheumatic heart disease, heart failure III NYHA and atrial fibrillation in 35% of cases. Mechanical heart valve prostheses were used in 70% of cardiac surgery cases. Real-time polymerase chain reaction was used for molecular genetic testing for polymorphisms VKORC, CYP2C9*2, CYP2C9*3, and CYP4F2. Results The frequencies of alleles and genotypes of CYP2C9 and VKORC1 in the study population of patients with heart valves prosthetic correspond to the distribution in Caucasian populations. Correlation between the calculated and actual therapeutic doses of warfarin was found according to the B.F Gage algorithm. In analyzing the dependence of the actual therapeutic dose of warfarin on polymorphic variants of the CYP2C9 and VKORC1 genes, it was shown that all the studied variants were associated with a therapeutic dose of warfarin, which was significantly different in carriers of different genotypes. Genotypes A/A CYP2C9*3 and G/G VKORC1 were associated with the largest deviations of the actual therapeutic dose from the calculated one. The clinical effectiveness of the pharmacogenetic approach was assessed according to the prevalence of the studied polymorphic variants of the CYP2C9 and VKORC1 genes in patients with prosthetic heart valves in the Kemerovo region. As a result, two groups of patients were formed using the “copy pair” method, without statistically significant differences in genetic, clinical, demographic, and anthropometric data. Usage of the pharmacogenetic testing at the beginning of warfarin therapy twice reduced time required to select a therapeutic dose of the anticoagulant, while the time within therapeutic INR range was increased by 20.2%. Conclusion The use of the panel-based pharmacogenetic approach at the beginning of warfarin therapy in patients with prosthetic heart valves increases the effectiveness and safety of anticoagulant therapy in the early postoperative period. Funding Acknowledgement Type of funding source: None

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