Comparison of Carbon Dioxide and Saline Flush to Saline Flush in TEVAR and TAVI Procedures to Reduce Cerebral Ischemia

Study Overview
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Brief Summary
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Thoracic endovascular repair (TEVAR) and transcatheter aortic valve implantation (TAVI) are standard of care procedures to treat thoracic aortic aneurysm or severe aortic stenosis, respectively. Both procedures have a high risk of stroke and silent infarction. Gas has been detected in the cerebral vasculature during these procedures and associated with DWI positive lesions on MRI. The hypothesis is that air emboli contribute to stroke and silent infarction. The investigators propose addressing air emboli by flushing the device with carbon dioxide prior to flushing with saline. This is a pilot study comparing standard saline flush alone to carbon dioxide flushing with saline flush.

Official Title
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Comparison of Carbon Dioxide Flush and Saline Flush to Saline Flush Alone in TEVAR and TAVI Procedures to Reduce Cerebral Ischemia

Conditions
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Thoracic Aortic Aneurysm, Aortic Stenosis Symptomatic, Stroke, Complication

Intervention / Treatment
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* Procedure: Carbon Dioxide and Saline Flush
* Procedure: Standard Saline Flush


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Elective TEVAR or TAVI Over 18 years old Exclusion Criteria: Recent acute myocardial infarction Recent stroke or TIA Post or pending organ transplantation Active peptic ulcer disease Recent gastrointestinal bleed History of bleeding diathesis or coagulopathy or contraindications to antiplatelet or anticoagulant therapy. Permanent pacemaker or ICD History of atrial fibrillation Moderate or severe allergy to iodinated contrast not amenable to predmedication Renal failure Unable to safely undergo MRI Enrollment in another study

Ages Eligible for Study
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Minimum Age: 18 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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Saline Flush<br>This is the control arm. The TEVAR or TAVI device will be flushed with at least 60mL of standard saline to reduce bubbles in the reservoir prior to deployment. This is the standard of care. | Procedure: Standard Saline Flush<br>* Standard of care flushing of the TEVAR or TAVI device with normal saline.<br>* Other names: Core Valve Transcatheter Aortic Valve;|
| Experimental: Carbon Dioxide and Saline Flush<br>Carbon dioxide flush of the TEVAR or TAVI device followed by saline flush. | Procedure: Carbon Dioxide and Saline Flush<br>* The TEVAR or TAVI device will be flushed with approximately 1.2L of medical grade carbon dioxide using a 60mL syringe and connecting tubing. The reservoir will then be flushed with at least 60mL of standard saline prior to deployment to minimize bubbles in the saline.<br>* Other names: CoreValve Trascatheter Aortic Valve;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Complications | Infection, bleeding, stroke, pseudoaneurysm formation, etc. | 30 days | 
| All cause mortality | Post procedural death. | 30 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Stroke | Physical examination and magnetic resonance imaging (MRI) brain. | 7 days | 
| Silent Infarction | MRI brain. | 7 days |