Impact of Anesthesia on the Dimension of the Ascending Aorta

Study Overview
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Brief Summary
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The aim of this study is to evaluate the accuracy and reliability of intra-operative TEE after the induction of anesthesia when assessing proximal thoracic aorta diameters in a cohort of aortic aneurysm patients.

Detailed Description
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Dilatation of the ascending aorta often progresses silently in an asymptomatic patient, until an acute complication occurs (such as a dissection or rupture), which is directly related to the diameter of the aortic. To prevent these extremely harmful situations, aortic replacement surgery, as indicated by significant dilatation of the ascending aorta, could be the option of choice (1). The decision to perform elective surgery depends on the measurement of the thoracic aorta diameter, which would rely on the largest aortic dimension. Trans-thoracic echocardiography (TTE) is widely used to assess the aortic root (2), and results from computed tomography (CT) scans are used to evaluate the ascending aorta beyond the sinotubular junction (3, 4). Both these tests facilitate follow-up evaluation of patients with thoracic aortic aneurysm. Usually, patients are referred for surgery based on the findings of one or both of these examinations. Furthermore, when a patient is referred for surgery, intra-operative trans-esophageal echocardiography (TEE) is often performed after induction of the anesthesia in order to evaluate the aortic dimension and valve function. In some cases, the diameter of the aorta is considered borderline for replacement, in which case the TEE measurement could reverse the decision-making, especially when the indication for surgery is due to valve pathology, with the aorta being a secondary consideration. From the investigators experience, intra-operative TEE aortic measurements after the anesthesia are not entirely accurate, and could under-estimate the diameter of the aorta. Relying on intra-operative TEE measurements could result in under-treatment of the dilated aorta, especially when its replacement is secondary to other cardiac pathologies (e.g. AVR, CABG) that require surgery. Influence of intra-operative anesthesia on TEE measurements of the aorta are not described in the current literature. If the investigators hypothesis is correct, adjustments will need to be made regarding the surgical management of patients with borderline aortic dimensions.

Official Title
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Prospective Study to Examine the Impact of Anesthesia on the Dimension of the Ascending Aorta in Patients With a Dilated Aorta Who Undergo Open-heart Surgery

Conditions
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Aortic Aneurysm, Thoracic

Intervention / Treatment
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* Other: Trans-esophageal echocardiography


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Ascending aorta of 40 mm and above Patients who undergo cardiac surgery Exclusion Criteria: Unstable patients Patients who underwent a previous cardiac surgery Patients who were diagnosed with aortic dissection

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 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: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Aorta dilated<br>Patients with aorta of 40mm or more who undergo a cardiac surgery. The intervention include: Trans-Esophageal Echocardiography | Other: Trans-esophageal echocardiography<br>* Perform a trans-esophageal echocardiography before and after anesthesia.<br>* Other names: Cardiac surgery;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| difference in the aortic dimension | 10% difference in the aortic dimension before and after anaesthesia | intraoperative |