Study supported by the Center for Mathematical Sciences Applied to Industry aims to improve device for cardiovascular treatments
Researchers from the University of São Paulo ( USP ) and the State University of Campinas ( Unicamp ) seek to improve the Wheatley aortic valve , a device that could help the lives of millions of people affected by aortic stenosis, a narrowing of the opening of the aortic valve that blocks the flow of blood from the left ventricle to the aorta.
Aortic stenosis is common among the elderly and, in severe cases, the only viable alternative to guarantee an improvement in the patient's quality of life is a transplant of the dysfunctional natural valve with an artificial one.
The studies have already won this year's USP Post-Doc Award in the area of exact and earth sciences for Dr. Hugo Luiz Oliveira , professor at Unicamp and participant in the group of researchers.
The improvement of the Wheatley aortic valve is important because it should eliminate the need for anticoagulant medications in the postoperative phase, as is the case with other polymeric valves.
Anticoagulants are used to 'thin' the blood, that is, they prevent the formation of clots and facilitate blood circulation. This type of drug treatment requires extreme care and attention from the patient, especially when bleeding occurs that can lead to other complications.
The research, developed within the scope of the Center for Mathematical Sciences Applied to Industry ( CeMEAI ), consists of computational modeling of the device that replaces the natural aortic valve in patients with severe cases of the disease. CeMEAI is a Research, Innovation and Diffusion Center ( CEPID ) supported by the São Paulo Research Foundation ( FAPESP ) and headquartered at the Institute of Mathematical and Computing Sciences of the University of São Paulo ( ICMC-USP ), São Carlos campus.
CeMEAI's research focuses on the Wheatley aortic valve, created in 2012 by Scottish professor and heart surgeon Dr. David Wheatley , because the inventor himself felt the need for a better understanding of the mathematical and computerized model of the device. The study opportunity for Brazilian researchers arose when Professor Wheatley consulted Dr. Sean McKee , from the University of Strathclyde , also in the United Kingdom. In turn, Dr. McKee contacted a former doctoral student under his supervision, USP professor José Alberto Cuminato , coordinator of CeMEAI, who currently belongs to the faculty at the University of Strathclyde.
Computational model
Having a high-fidelity computational model reduces not only the time spent designing the valve and its intrinsic mechanisms, but also the costs involved in the physical production of prototypes and experimental tests.
The CeMEAI team proposed to carry out computational modeling of the Wheatley valve in order to reproduce its mechanical behavior under service conditions. This action allows any improvements identified to be tested virtually (in silico) without the need to produce new parts for each proposed change.
The experiments aim to ensure that the valve opens and closes quickly and that the shear stress in the blood flow is always above a critical threshold. As a result, the system prevents the formation of thrombosis and guarantees a longer useful life of the device compared to conventional valves.
To achieve the proposed result, the researchers tested several software. The option that best suited the needs of the research project was the LS-DYNA solver , which allowed the computer to reproduce the mechanical and fluid dynamic performance that Wheatley's aortic valve presents under controlled flow and pressure conditions.
Access the full news on the Agência FAPESP page .
Source: CeMEAI Communications Office and Agência FAPESP.
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