Post-surgical Aortic Hemodynamics After Aortic Valve Replacement

Study Overview
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Brief Summary
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The purpose of this pilot study is to obtain both near valve and downstream flow characteristics, using 3D transthoracic echocardiography and 4D flow MRI respectively, in an existing patient population at Northwestern Memorial Hospital, to determine the hinge washout characteristics and downstream flow patterns of the On-X valve and compared to competing designs.

Detailed Description
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Prospective, concurrent 4D flow Magnetic Resonance Imaging (MRI) and echocardiography of On-X and St Jude Medical (SJM) Masters HP or Carbomedics Carbo-seal or Carbo-seal Valsalva aortic valve replacement (AVR) patients will be performed. Echocardiography analysis will include: valve function (opening angle), pressure gradients, and degree of valve washout. MRI analysis will focus on downstream flow patterns (helicity and vorticity), energy loss, pressure recovery, and measurement of wall shear stress in the anastomosis regions.

Official Title
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Investigation of Post-surgical Aortic Hemodynamics After Aortic Valve Replacement

Conditions
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Valve Heart Disease

Intervention / Treatment
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* Other: MRI
* Other: Transthoracic echocardiography exam


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Male and female subjects 18-89 years of age Patients with aortic valve disease who within the last five years underwent AVR using the On-X aortic valve, SJM Masters HP, or Carbomedics aortic valves. Exclusion Criteria: Patients contraindicated against MRI Patients with pacemakers, cochlear (in the ear) implants, or aneurysm clips or patients who have worked with metal Patients unwilling or unable to give written informed consent Pregnant women Prisoners Patients with an Effective Orifice Area index (EOAi) <0.85 cm2/m2

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 89 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| On-X AAP<br>Patients with prior AVR surgery with the CryoLife On-X Ascending Aortic Prosthesis (AAP). | Other: MRI<br>* Enrolled patients will complete a non-contrast cardiac MRI<br>Other: Transthoracic echocardiography exam<br>* Enrolled patients will complete a transthoracic echocardiography exam.<br>|
| SJM Masters or Carbomedics Carbo-seal<br>Patients with St. Jude Medical Masters HP Valved Graft with Gelweave Valsalva™ Technology or Carbomedics Carbo-seal (including Carbo-seal Valsalva) mechanical aortic valve prostheses patients | Other: MRI<br>* Enrolled patients will complete a non-contrast cardiac MRI<br>Other: Transthoracic echocardiography exam<br>* Enrolled patients will complete a transthoracic echocardiography exam.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Downstream flow patterns (helicity and vorticity) | MRI data analysis; Helicity and vorticity graded (1-3) by blinded reviewers. | 3 months | 
| Hinge washout | MRI data analysis; Yes/No | 3 months | 
| Energy loss | MRI data analysis; Irreversible energy loss quantified.Efforts will include the quantification of turbulent kinetic energy. This is representative of permanent pressure loss. | 3 months | 
| Wall shear stress (WSS) | MRI data analysis; WSS, the tangential force exerted by blood flow on the vessel wall, measured in the anastomosis regions | 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ejection Fraction (%) |  | 3 months | 
| Primary EDV (ml) | End Diastolic Volume | 3 months | 
| Normalized EDV (ml/m^2) | End Diastolic Volume | 3 months | 
| Primary ESV (mL) | End Systolic Volume | 3 months | 
| Normalized ESV (mL/m^2) | End Systolic Volume | 3 months | 
| Peak Velocity (m/s) |  | 3 months | 
| Mean velocity (m/s) |  | 3 months | 
| Peak transvalvular pressure gradient (mmHg) |  | 3 months | 
| Mean transvalvular pressure gradient (mmHg) |  | 3 months | 
| Effective Orifice Area (EOA) |  | 3 months | 
| Effective Orifice Area index (EOAi) |  | 3 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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mechanical heart valve, On-X