Mechanical Characterization of Ascending Aorta in Patients With and Without Aortic Dissection
Mechanical Characterization of Ascending Aorta in Patients With Acute Type A Dissection and in Healthy Control Group Combined to Structural and Ultrastructural Analysis of Aortic Tissue
調査の概要
詳細な説明
Objectives: this study aims to characterize mechanical properties of ascending aorta (AA) in patients, with and without aortic dissection.
Materials and methods : comprised an in vivo and ex vivo studies performed in 2 groups of patients : (1) patients admitted for acute type A dissection and treated with surgical procedure ; (2) healthy control group selected among patients without any ascending aorta pathology and who underwent transoesophageal echocardiography for various indications.
In vivo study : Strain, distensibility, stiffness index and pressure strain elastic modulus (Ep) were calculated from aortic diameter variation in response to pressure variation. Aortic diameters were measured using transoesophageal echocardiography.
Ex vivo study : biaxial tensile testing were performed on aortic wall samples. Dissected aortic samples were collected from patients who underwent surgical repair and healthy samples from unused donors hearts and lungs. Mechanical characterization was combined to a histological and microstructural analysis of aortic wall. The latter was conducted using multiphoton microscopy to visualize elastin and collagen fibers.
Results :
In vivo study: 22 patients in healthy control group and 13 patients in dissection group were prospectively investigated.
In vitro study : Biaxial testing was performed on 4 samples of dissected aorta and 6 samples of non dissected aorta. Anisotropic and non linear behavior of aortic tissue was shown in the 2 types of samples. Dissected tissue were stiffer than the intimal flap which was in turn stiffer than non dissected tissue.
Histological data showed that in dissection group global elastin density was lower than in control. Microstructural analysis in dissection specimens revealed a higher collagen signal in the media mainly in circumferential plane, contrasting with a roughly similar intensity between the two planes in control. This higher signal reflects higher collagen fiber density and/or thicker fibers in this tunica.
Conclusion : Both in vivo and in vitro data revealed that dissected aorta was stiffer than healthy ascending aorta. These findings has consequences on the choice of futur devices dedicated to AA
研究の種類
入学 (予想される)
連絡先と場所
研究場所
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Marseille、フランス、13354
- 募集
- Assistance Publique Hôpitaux de Marseille
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コンタクト：
- Mourad BOUFI
- 電話番号：+33 0491382747
- メール：drci@ap-hm.fr
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参加基準
適格基準
就学可能な年齢
健康ボランティアの受け入れ
受講資格のある性別
サンプリング方法
調査対象母集団
説明
Inclusion Criteria:
- Patients aged 50 to 85 years
- The information given search,
- Aortic dissection evolving for less than 15 days confirmed
Exclusion Criteria:
- the acute aortic dissections against-indicated for aortic surgery (patient age, stroke or multiple organ failure)
- Iatrogenic dissections,
- Dissections related to congenital or hereditary disorder (abnormal connective tissue) or those occurring in subjects with a bicuspid aortic valve,
- Intramural hematomas type A,
- Patients under guardianship or trusteeship deprived of liberty.
研究計画
研究はどのように設計されていますか？
デザインの詳細
- 時間の展望：見込みのある
コホートと介入
グループ/コホート |
介入・治療 |
|---|---|
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experimental
patients with acute type A dissection
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control
patients without any pathology of the ascending aorta, but having the same characteristics as the sick patients, in terms of age and vascular risk factors including high blood pressure
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この研究は何を測定していますか？
主要な結果の測定
結果測定 |
メジャーの説明 |
時間枠 |
|---|---|---|
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measure the elastic properties of aortic wall
時間枠：one day
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The distensibility, aortic strain will be measured as a function of changes of aortic diameter and pulse pressure.
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one day
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Measurement of aortic diameters
時間枠：one day
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The measurement will be done by transesophageal echocardiography simultaneously to the cuff brachial artery pressure.
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one day
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協力者と研究者
研究記録日
主要日程の研究
研究開始
一次修了 (実際)
研究の完了 (予想される)
試験登録日
最初に提出
QC基準を満たした最初の提出物
最初の投稿 (見積もり)
学習記録の更新
投稿された最後の更新 (見積もり)
QC基準を満たした最後の更新が送信されました
最終確認日
詳しくは
本研究に関する用語
その他の研究ID番号
- 2013-08
この情報は、Web サイト clinicaltrials.gov から変更なしで直接取得したものです。研究の詳細を変更、削除、または更新するリクエストがある場合は、register@clinicaltrials.gov。 までご連絡ください。 clinicaltrials.gov に変更が加えられるとすぐに、ウェブサイトでも自動的に更新されます。