Numerical simulation of leaflet flexure in bioprosthetic valves mounted on rigid and expansile stents

Krucinski, S.; Veselý, Ivan; Dokainish, M. A.; Campbell, Gordon

doi:10.1016/0021-9290(93)90055-j

Cited by 76 publications

(41 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…23,31 Cusp ruptures, inducing relatively sudden but significant valve regurgitation, can be seen as "fatigue damage" due to buckling and tension of the glutaraldehyde cross-linked collagen of the leaflets. 32 Our finding that all valve models are prone to this kind of wear after Ϸ10 years of implantation, irrespective of the valve model, valve size, or presence of P-PtM, is not surprising because all of these different valve types, although carefully designed, are glutaraldehyde crosslinked. When these valves finally will wear and rupture in ex vivo accelerated fatigue cycling tests, why should they not do this after 30 to 40 million cycles in vivo?…”

Section: Svd and Mode Of Valve Failurementioning

confidence: 83%

Prosthesis-Patient Mismatch Predicts Structural Valve Degeneration in Bioprosthetic Heart Valves

et al. 2010

View full text Add to dashboard Cite

Background-Prosthesis-patient mismatch (P-PtM) after aortic valve replacement results in disturbed valve performance associated with increased pressure gradients. However, it is unknown whether this can be related to future structural valve deterioration (SVD) of the bioprosthesis. Methods and Results-In 564 patients (mean age, 74Ϯ5 years) receiving an aortic valve bioprosthesis, clinical follow-up (median, 6.1 years; maximum, 16.4 years) was analyzed including echocardiography. SVD was diagnosed in 40 patients (7%) as substantially increased stenosis (nϭ24) or regurgitation (nϭ16) of the operated valve over time. When patients with P-PtM (effective orifice area index Ͻ0.85 cm 2 /m 2 ; nϭ285) developed SVD, it was preferentially of the stenosis type, whereas when patients without P-PtM (nϭ279) developed SVD, the majority was of the incompetence type (PϽ0.05). Multivariable analysis including patient-and valve-related variables revealed that P-PtM and label size Յ21 were independent predictors of SVD (Pϭ0.04 and Pϭ0.02, respectively). A nonparametric Turnbull estimate analysis showed that SVD is virtually nonexistent for up to 9 years in patients without P-PtM. Thereafter, SVD starts to occur and is mainly of the incompetence-type SVD (79% of cases). In patients with P-PtM, SVD starts to occur after 2 to 3 years after implantation and is mainly of the stenosis-type SVD (81% of cases). Conclusions-These data suggest that stenosis-type SVD is an early, P-PtM-related, and thus preventable phenomenon.Incompetence-type SVD is a time-dependent, nonspecific wear damage to bioprosthetic valves, which is not related to P-PtM. (Circulation. 2010;121:2123-2129.)

show abstract

Section: Svd and Mode Of Valve Failurementioning

confidence: 83%

Prosthesis-Patient Mismatch Predicts Structural Valve Degeneration in Bioprosthetic Heart Valves

et al. 2010

View full text Add to dashboard Cite

show abstract

“…Finite element stress analyses of BHV suggests that high exural stresses during valve opening and high tensile stresses during valve closure are associated with failure locations (Hamid et al, 1986;Black et al, 1991;Krucinski et al, 1993). Their accuracy, however, is limited by the use of simplistic isotropic material approximations, since in reality lea¯ets are anisotropic biocomposite materials (Sacks and Chuong, 1998).…”

Section: Introductionmentioning

confidence: 97%

A structural constitutive model for chemically treated planar tissues under biaxial loading

Sacks

2000

Computational Mechanics

View full text Add to dashboard Cite

Chemically treated, biologically derived soft collagenous tissues are used extensively in medical devices. To enable prosthesis design through computational methods, physically realistic constitutive models are required. In the present study, a structural approach was utilized that incorporated experimentally measured angular distribution of collagen ®bers. Using biaxial mechanical data from our previous study (Annals of Biomedical Engineering, vol. 26(5), pp. 892±902, 1998), the effective ®ber and matrix stress±strain responses were predicted. The agreement with the experimental data supported the assumption that the mechanical effects of chemical treatment are equivalent to the addition of an isotropic elastic matrix. An important utility of this model is its ability to separate the effects of chemical treatment on the ®bers and matrix. Applications of this approach include utilization in the design of novel chemical treatments that produce speci®c mechanical responses, the study of fatigue damage, and ®nite element implementation for tissue engineering scaffold design.

show abstract

“…In addition, studies on surgical bioprostheses have shown that flexible leaflet attachment line or stent, with radial stent deflection, reduces the peak stress on valve leaflets. 6,7,9,17 However, for PAV the tubular stent structure does not permit radial stent deflection. Lack of radial stent deflection might be one of the main faulty designs of the Ionescu-Shiley pericardial valve, 8,9 which had an unacceptable rate of structural failure and was withdrawn from the market.…”

Section: Introductionmentioning

confidence: 99%

Simulated Thin Pericardial Bioprosthetic Valve Leaflet Deformation Under Static Pressure-Only Loading Conditions: Implications for Percutaneous Valves

Sun

2010

Ann Biomed Eng

104

View full text Add to dashboard Cite

Percutaneous aortic valve (PAV) replacement is currently being investigated as an endovascular alternative to conventional open-chest valve surgery for patients with severe aortic stenosis. The results of multi-center clinical trials of PAV devices have been encouraging. However, there are serious adverse events associated with this procedure. Furthermore, long-term durability and safety of PAV need to be studied carefully. In this study, we developed a thin pericardial bioprosthetic valve model, which has similar design features of PAV. We utilized this model to investigate PAV deformation under static, pressure-only loading conditions using Finite Element method. Mechanical properties of PAV leaflet were obtained from planar biaxial testing of glutaraldehyde treated thin bovine pericardium (BP) and porcine pericardium (PP), and characterized by the Fung-elastic model. Simulations were performed to examine the effects of tissue thickness and anisotropy on the valve deformation and stress distribution. The results indicated peak stress and strain occurred in the vicinity of commissures. The peak maximum principal stresses (MPS) were reduced with the increase of leaflet tissue thickness, by 36% and 59% from the mean thickness to 0.35 mm for BP and PP, respectively. The PAV with BP leaflet had a lower peak MPS than that with PP leaflet. Moreover, leaflet material orientation had a significant influence on the peak MPS of PAV.

show abstract

Numerical simulation of leaflet flexure in bioprosthetic valves mounted on rigid and expansile stents

Cited by 76 publications

References 42 publications

Prosthesis-Patient Mismatch Predicts Structural Valve Degeneration in Bioprosthetic Heart Valves

Prosthesis-Patient Mismatch Predicts Structural Valve Degeneration in Bioprosthetic Heart Valves

A structural constitutive model for chemically treated planar tissues under biaxial loading

Simulated Thin Pericardial Bioprosthetic Valve Leaflet Deformation Under Static Pressure-Only Loading Conditions: Implications for Percutaneous Valves

Contact Info

Product

Resources

About