CFD, Valve Heart Disease
Conditions
Keywords
Bioprosthesis
Brief summary
Bioprosthetic valves are usually made of biological tissue that are mounted to a frame and are designed to function similarly to a healthy natural valve. Edwards Magna Ease and Intuity Elite bioprosthetic valves have similar leaflets and mounting designs. However, the valves are implanted in the patient in different ways (one is stitched to the wall of the left ventricular outflow tract, and the other is held in place by the radial force of the valve skirt). The study aims to understand in more detail how the different valves interact with the left ventricular outflow tract and aortic root.
Detailed description
The implantation of a bioprosthetic valve is the established surgical technique when replacing the aortic valve to treat various aortic valve diseases. Many different bioprosthetic valves are available. The design and implantation technique in each system would result in different interaction with the left ventricular outflow tract (LVOT) and the aortic root, leading to different flow profiles that may induce platelet aggregation and affect the long-term performance of the bioprosthesis and its durability. Additionally, complications such as valve thrombosis may occur. However, it is not currently clear which bioprostheses/patients are more prone to thrombosis or degradation of the valve. This study aims to develop fluid-structure interaction (FSI) models, which can model blood flow and wall/valve mechanics, using realistic patient-specific geometries and flow conditions which correlate with the true performance of the valve in the imaged patients, and to assess and compare such performances to understand the benefits and challenges with various bioprosthetic valves. FSI models combine computational fluid mechanics (CFD) with structural wall mechanics modelling. This is an alternative approach that allows detailed assessment of flow patterns and estimation of wall shear stress and pressure within blood vessels, and therefore has been applied increasingly to gain better insights into the hemodynamics in cardiovascular diseases
Interventions
DIAGNOSTIC_TESTComputed Tomography, Magnetic Resonance Imaging
Computed Tomography, Magnetic Resonance Imaging
Sponsors
Edwards Lifesciences
Imperial College London
Royal Brompton & Harefield NHS Foundation Trust
Study design
Observational model
CASE_ONLY
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Male and female patients aged 18 years or over. * Patients diagnosed with aortic valve disease, and scheduled to undergo Edwards Magna Ease or Intuity Elite and free of
Exclusion criteria
below. * The patient is willing and able to understand the Patient Information Sheet and provide written informed consent. * The patient must agree to comply with the study imaging protocol as required at prespecified times.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| blood flow velocities | 12 months | Blood flow velocities (cm/s) will be quantified for each bioprosthesis at 3 levels: subvalvular (LVOT and native annulus), transvalvular, the aortic root, and the proximal ascending aorta. Velocities more than 20cm/s will be taken as abnormal. |
| Time average wall shear stress (TAWSS) | 12 months | TAWSS will be quantified for each bioprosthesis at 3 levels: subvalvular (LVOT, the aortic root, and the proximal ascending aorta. TAWSS under 0.5Pa is taken as low, 0.51-2.0 as moderately increased, \>2.0 Pa as severely increased TAWSS. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Patient's satisfaction | 12 months | A questionnaire will be designed to score valve-related clinical symptoms following the intervention. |
| Evidence of major adverse cardiac and cerebrovascular events (MACCE) | 12 months | Evidence of MACCE (Stroke and myocardial infarction in the first 12 months post procedure) |
| Mortality | 12 months | Evidence of mortality during the 12 months post procedure. |
Contacts
Primary ContactSaeed Mirsadraee, MD, Ph.D
Outcome results
None listed