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find Keyword "heart valve" 37 results
  • Technological development frontier and future trend of cardiovascular surgery

    In recent years, the field of cardiovascular surgery has undergone revolutionary changes and made rapid progress in various aspects, bringing more hope and possibilities for the health and well-being of patients. The constant emergence of new technologies brings new opportunities and hope, as well as constant challenges to past concepts. This article aims to provide a comprehensive overview of the latest developments in cardiovascular surgery in recent years, especially since 2023. It introduces cutting-edge knowledge and technologies in the field of cardiovascular surgery, including lifelong management of aortic valve disease, artificial valves, mitral valves, treatment options for hypertrophic obstructive cardiomyopathy, heart transplantation, left ventricular assist, coronary artery surgery, cardiac structural interventions for chronic heart failure, aortic dissection, and comprehensive surgical treatment of atrial fibrillation. It also analyzes and explores future development directions in depth, aiming to provide useful references and inspiration for cardiovascular doctors and jointly promote the continuous progress of cardiovascular surgery in China.

    Release date:2024-12-25 06:06 Export PDF Favorites Scan
  • The history of pulsatile flow experiment of prosthetic heart valve: The 70th anniversary of the application of prosthetic heart valves

    The pulsatile flow experiment can not only evaluate the preclinical safety and risk of prosthetic heart valve (PHV) but also play an important role in the computational model and fluid simulation, providing an experimental basis for the performance optimization of PHV. This paper mainly reviews the development and the latest progress of PHV pulsatile flow experiments and the characteristics of experimental pulse duplicator, and discuss the research direction of pulsatile flow experiments, expecting a further development in this field.

    Release date:2024-02-20 04:11 Export PDF Favorites Scan
  • PREPARATION OF ACELLULARIZED PORCINE HEART VALVE AND SEEDING OF BOVINE AORTIC ENDOTHELIAL CELLS

    OBJECTIVE: To explore the possibility of detergent acellularized porcine heart valve serving as a scaffold for tissue engineering valve. METHODS: The porcine aortic valves were acellularized by use of trypsin-EDTA. Triton X-100, RNase and DNase treatment. Biomechanical characteristics of fresh valves and acellularized valve were tested; also fresh valves, acellularized valve and valves treated with method of bioprothetic treatment were implanted subcutaneously in rats; frequently seeded with bovine aortic endothelial cells(BAECs), and then cultured for 7 days. RESULTS: The acellularization procedure resulted in complete removal of the cellular components while the construction of matrix was maintained. The matrix could be successfully seeded with in vitro expanded BAECs, which formed a continuous monolayer on the surface. There is no significant difference of PGI2 secretion of BAECs between cells seeded onto the acellular leaflets and that onto the wells of 24-wells plate (P gt; 0.05). CONCLUSION: Acellularied porcine aortic valve can be applied as a scaffold to develop tissue engineering heart valve.

    Release date:2016-09-01 09:35 Export PDF Favorites Scan
  • Research progress of transcatheter aortic valve replacement-related new valve prostheses

    Transcatheter aortic valve replacement has revolutionized the management of aortic stenosis and become the gold standard for the treatment of symptomatic and severe aortic valve stenosis in elderly patients. With the improvement in design and materials, newer generation transcatheter aortic valve prostheses had overcome the limitations of early-generation devices that were susceptible to paravalvular leak, atrioventricular block and vascular complications, to a certain extent. This review provides an update on the latest advances in transcatheter aortic valve prostheses.

    Release date:2023-09-28 02:17 Export PDF Favorites Scan
  • Analysis of factors for international normalized ratio levels>3.0 in patients undergoing warfarin anticoagulation therapy after mechanical heart valve replacement

    ObjectiveTo investigate the factors influencing international normalized ratio (INR)>3.0 in patients undergoing warfarin anticoagulation therapy after mechanical heart valve replacement. MethodsA retrospective analysis was performed on the clinical data of patients who underwent mechanical heart valve replacement surgery and received warfarin anticoagulation therapy at West China Hospital of Sichuan University from January 1, 2011 to June 30, 2022. Based on the discharge INR values, patients were divided into two groups: an INR≤3.0 group and an INR>3.0 group. The factors associated with INR>3.0 at the time of discharge were analyzed. ResultsA total of 8901 patients were enrolled, including 3409 males and 5492 females, with a median age of 49.3 (43.5, 55.6) years. The gender, body mass index (BMI), New York Heart Association (NYHA) cardiac function grading, INR, glutamic oxaloacetic transaminase, and preoperative prothrombin time (PT) were statistically different between the two groups (P<0.05). Multivariate logistic regression analysis revealed that lower BMI, preoperative PT>15 s, and mitral valve replacement were independent risk factors for INR>3.0 at discharge (P<0.05). ConclusionBMI, preoperative PT, and surgical site are factors influencing INR>3.0 at discharge in patients undergoing warfarin anticoagulation therapy after mechanical heart valve replacement. Special attention should be given to patients with lower BMI, longer preoperative PT, and mitral valve replacement to avoid excessive anticoagulation therapy.

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  • Research Status and Development Trends of the Heart Valve Mechanical Properties

    The study of mechanical properties on heart valves can provide an important theoretical basis for doctors to repair heart valves and prosthetic valve materials research. In this paper, we present the current status of the mechanical property study methods of heart valve, expound the methods and special requirements about uniaxial tensile test and biaxial tensile test of the heart valve, and further discuss several establishment methods of heart valve constitutive models. We also discuss the development trend of heart valve mechanics.

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  • The value of right atrial myocardial fibrosis in evaluating the prognosis of isolated tricuspid valve surgery after left heart valve surgery

    ObjectiveTo investigate the predictive value of right atrial myocardial fibrosis in the prognosis of isolated tricuspid regurgitation surgery after left heart valve surgery. MethodsThe patients who underwent tricuspid valvuloplasty by the same operator in Guangdong Provincial People's Hospital from April 2016 to August 2021 due to long-term isolated severe tricuspid regurgitation after left heart valve surgery were included in the study. According to the degree of right atrial myocardial fibrosis, the patients were divided into three groups: a mild group, a moderate group, and a severe group. The clinical data of these patients were compared and analyzed. ResultsA total of 75 patients were enrolled, including 16 males and 59 females with an average age of 57.0±8.4 years. There were 30 patients in the mild group, 29 patients in the moderate group and 16 patients in the severe group. In terms of the preoperative data, there were statistical differences in cardiac function grade, right atrial diameter, tricuspid incompetence area among the three groups (P<0.05). In terms of the postoperative data, there were statistical differences among the three groups in the cardiopulmonary bypass time, mechanical ventilation time, ICU monitoring time, complication rate and mortality (P<0.05). Further pairwise comparison showed that, compared with the mild group, the severe group had longer mechanical ventilation time (P=0.024), longer ICU monitoring time (P=0.003) and higher incidence of postoperative complications (P=0.024), while the moderate group had no statistical difference in all aspects (P>0.05); compared with the moderate group, the severe group had longer ICU monitoring time (P=0.021) and higher incidence of complications (P=0.006). ConclusionThe early outcome of tricuspid valvuloplasty in patients with isolated tricuspid regurgitation after left heart valve surgery with severe right atrial myocardial fibrosis is worse than that in the patients with mild and moderate fibrosis, suggesting that the degree of myocardial fibrosis in the right atrium can be a predictor of the effect of tricuspid regurgitation surgery and a judgement indicator of the surgery timing.

    Release date:2023-07-10 04:06 Export PDF Favorites Scan
  • Reason Analysis and Prevention of Late Bioprosthetic Heart Valve Thrombosis

    ObjectiveTo analyze the reason and prevention of late bioprosthetic heart valve thrombosis (LBVT). MethodsBioprosthetic heart valves were implanted in 580 patients between January 2001 and July 2013 in Changhai Hospital, and only found one case of LBVT (0.2%). Reoperation was performed for a 67-year-old male patient 3 years after bioprosthetic aortic valve replacement due to severe aortic valve stenosis. Retrospectively analyzed the clinical data and reviewed the literature between January 1989 and December 2013 in Pubmed. ResultsNo risk factor for thrombosis was revealed in this patient. Pathology revealed valve thrombosis and collagen and elastic fibers fragmentation and disruption in valve leaflets. In literature review, 20 articles and 47 cases were brought in. The morbidity of LBVT was 0.2%-1.0%. At least 18 patients had high risk factors, and 15 of the 18 patients discontinued anticoagulation after 3 months. However, at least 10 patients had no high risk factors. Forty-four of the 47 patients received stented porcine valve replacement, only one patient received stented bovine pericardial valve replacement. ConclusionsLBVT is a rare but serious complication after bioprosthetic valve replacement, the causes of which include the feature of the patients and the bioprosthetic valves. Bovine pericardial valves could be superior to porcine valves in preventing LBVT. Postoperative long-time aspirin therapy is recommended for patients without high risk factors. Patients with any high risk factors should prolong anticoagulation.

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  • Advances in transcatheter aortic valve replacement for pure aortic regurgitation

    Transcatheter aortic valve replacement (TAVR) for aortic stenosis has been confirmed to be safe and efficient, and its status has gradually increased with the continuous updating of guidelines. But for severe pure aortic valve regurgitation, it has long been considered a relative contraindication to TAVR. However, many elderly, high-risk patients with pure aortic regurgitation have also been treated with TAVR and prognosis was improved through off-label use of transcatheter heart valves due to contraindications to surgery or intolerance. But because of the complexity and challenging anatomic features, high technical requirements, limited device success rate, high rate of complications, and lack of randomized controlled studies to confirm its safety and efficacy, TAVR treatment of pure aortic regurgitation has been evolving in a debate. In recent years, with the application of new-generation valves and an increasing number of studies, some new insights have been gained regarding TAVR for severe aortic regurgitation, and this article will review the progress of research on TAVR for severe pure aortic regurgitation.

    Release date:2022-05-23 10:52 Export PDF Favorites Scan
  • Biocompatibility of bioprosthetic heart valve materials with a non-glutaraldehyde-based chemical treatment

    ObjectiveTo study the biocompatibility of bioprosthetic heart valve material with a non-glutaraldehyde-based treatment, and to provide the safety data for the clinical application. MethodsAll the tests were conducted according to GB/T16886 standards. The in vitro cytotoxicity was determined by methyl thiazolyl tetrazolium assay. Fifteen guinea pigs were divided into a test group (n=10) and a control group (n=5) in the skin sensitization test. Three New Zealand white rabbits were used in the intradermal reactivity test. Five sites on both sides of the rabbit back were set as test sites and control sites, respectively. In the acute systemic toxicity test, a total of 20 ICR mice were randomly assigned to 4 groups: a test group (polar medium), a control group (polar medium), a test group (non-polar medium) and a control group (non-polar medium), 5 in each group. Forty SD rats were divided into a test group (n=20) and a control group (n=20) in the subchronic systemic toxicity test. ResultsThe viability of the 100% extracts of the bioprosthetic heart valve material with a non-glutaraldehyde-based treatment was 75.2%. The rate of positive reaction was 0.0%. The total intradermal reactivity test score was 0. There was no statistical difference in the body weight between the test group and control group in the acute systemic toxicity test. There was no statistical difference in the body weight, organ weight, organ weight/body weight ratio, blood routine test or blood biochemistry between the test group and control group in the subchronic systemic toxicity test. ConclusionThe bioprosthetic heart valve material with a non-glutaraldehyde-based treatment has satisfying biocompatibility, which conforms to relevant national standards. The material might be a promising material for application in valve replacement.

    Release date:2022-12-28 06:02 Export PDF Favorites Scan
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