Prosthetic Aortic Valves: Challenges and Solutions.
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ABSTRACT:
SUBMITTER: Musumeci L
PROVIDER: S-EPMC5961329 | biostudies-literature | 2018
REPOSITORIES: biostudies-literature
Publications
Prosthetic Aortic Valves: Challenges and Solutions.
Musumeci Lucia L Jacques Nicolas N Hego Alexandre A Nchimi Alain A Lancellotti Patrizio P Oury Cécile C
Frontiers in cardiovascular medicine 20180514
Aortic Valve Disease (AVD) is the most common Valvular Heart Disease (VHD), affecting millions of people worldwide. Severe AVD is treated in most cases with prosthetic aortic valve replacement, which involves the substitution of the native aortic valve with a prosthetic one. In this review we will discuss the different types of prosthetic aortic valves available for implantation and the challenges faced by patients, medical doctors, researchers and manufacturers, as well as the approaches that a ...[more]
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Project description:Implantation of prosthetic valve requires consideration for anticoagulation. The current guideline recommends warfarin on all mechanical valves. Dabigatran is the new generation anticoagulation medication which is taken orally and does not require frequent monitoring. This drug is approved for treatment for atrial fibrillation and venous thromboembolism, but the latest large trial showed that this drug increases adverse events when used for mechanical valve anticoagulation. On-X valve is the new generation mechanical valve which is considered to require less anticoagulation due to its flow dynamics. The latest study showed that lower anticoagulation level lowers the incidence of bleeding, while the risk of thromboembolism and thrombosis remained the same. Anticoagulation poses dilemma in cases such as pregnancy and major bleeding event. During pregnancy, warfarin can be continued throughout pregnancy and switched to heparin derivative during 6-12 weeks and >36 weeks of gestation. Warfarin can be safely started after 1-2 weeks of discontinuation following major bleeding episode.
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Project description:Although there are abundant data highlighting the safety and efficacy of direct oral anticoagulants, to date, recent guidelines have limited their use to stroke prevention in patients with non-valvular AF, as well as in the prevention and treatment of venous thromboembolism and pulmonary embolism. Encouraging data about the off-label use of direct oral anticoagulants have been shown in several other indications, such as intracardiac thrombi, left ventricular thrombi and left atrial appendage, but a large sector of patients are still not addressed, such as valvular and prosthetic patients.
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Project description:The aim of this study was to reveal the pathogenesis of aortic stenosis (AS) and regurgitation (AR) by comparing differences in mechanical and biochemical alterations. We applied scanning acoustic microscopy (SAM) to measure the speed of sound (SOS) through valves to estimate the elasticity and monitor sensitivity to protease treatment, as the SOS is correlated with the stiffness of materials, which is reduced after digestion by proteases. The fibrosa of both the AS and AR groups were stiffer than the fibrosa of the normal group. The AR group displayed significantly stiffer fibrosa than the AS group, with the exception of calcified areas. The AS group showed significantly decreased SOS values following protease digestion, whereas the AR showed little reduction. The AS group presented type III collagen in the fibrosa and the ventricularis. In the AR group, both type I collagen and type III collagen coexisted in the fibrosa and the ventricularis. Upon immunostaining for advanced glycation end-products, the AS group showed sparse, weak staining, whereas the AR group presented a strong, band-like positive reaction in the fibrosa. In conclusion, tissue remodelling associated with damage and repair is associated with AS pathogenesis, whereas static chemical alterations with slow collagen turnover induce AR.
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Project description:Valve interstial cells(VICs) are the major cellular compents in the aortic valve. Under pathological circumstances, normal VICs differentiate into myofibroblasts or osteoblast-like phentotypes, which play important roles in the pathogenesis of calcified aortic valve disease. We used micrroarrary analysis to compare the global programme of gene expression in normal and calcified human aortic valve intersitial cells (VICs), in order to find out some key factors that mediate the phenotype change of VICs.
2016-10-23 | GSE88803 | GEO
Project description:This original clinical research study id focused on description of baseline anatomy and outcomes after transcatheter aortic valve implantation (TAVI) in patients presenting with severe aortic stenosis (AS) and bicuspid aortic valve (BAV). We compared this BAV population with a population of patients with AS and tricuspid aortic valves after a propensity score matching developed by a multivariate logistic regression according to a non-parsimonious approach. Baseline anatomical characteristics were obtained by transthoracic echocardiography (TTE) and multi-sliced computed tomography (MSCT) and compared by chi-square and t-student tests. Outcomes were evaluated by correct fisher test at in hospital and 30 days follow-up. We found that BAV patients presents more complicated baseline anatomy as compared to patients with tricuspid valves. These anatomical features lead to higher procedural complications as the need for a second device implantation. However this does not translate into increase in mortality rate at 30 days follow-up but rather correlate to a lower device success rate.
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Project description:BackgroundAdvances in surgical technique, prosthetic heart valve design, and anticoagulation have contributed to an overall improvement in morbidity and mortality in women with heart valve prostheses as well as increased feasibility of pregnancy. Previous work investigating the pregnancies of women with prosthetic valves has been directed largely toward understanding the influence of anticoagulation regimen. There has been little investigation on maternal and infant outcomes. The objective of this systematic review will be to assess the outcomes of pregnancy in women with heart valve prostheses in contemporary populations.Methods/designA systematic search of Medline, Embase, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and the Cochrane Library will be undertaken. Article titles and abstracts will be evaluated by two reviewers for potential relevance. Studies that include pregnancies occurring from 1995 onwards and where there are six or more pregnancies in women with heart valve prostheses included in the study population will be reviewed for potential inclusion. Primary outcomes of interest will be mortality (maternal and perinatal). Secondary outcomes will include other pregnancy outcomes. No language restrictions will be applied. Methodological quality and heterogeneity of studies will be assessed. Data extraction from identified articles will be undertaken by two independent reviewers using a uniform template. Meta-analyses will be performed to ascertain risk of adverse events and, where numbers are sufficient, by type of prosthesis and location as well as other subgroup analyses.DiscussionEstimates of the risk of adverse events in recent pregnancies of women with heart valve prosthesis will provide better information for counselling and decision making. Given the improvements in prognosis of heart valve prosthesis recipients and the paucity of definitive data regarding optimal pregnancy management for these women, review of this topic is pertinent.Review registrationThis protocol has been registered with the international prospective register of systematic reviews (PROSPERO) as number CRD42013006187, accessible online at http://www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD42013006187#.Utk7qNJ9Lf8.
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