DK2985_C000 1..28 - AlSharqia Echo Club

12AortaIVAN IGLESIAS, DANIEL BAINBRIDGE, JOHN MURKINUniversity of Western Ontario, London, Ontario, CanadaALAN H. MENKISUniversity of Manitoba, Manitoba, CanadaI. Anatomical Considerations 261II. Transesophageal Echocardiography as aDiagnostic Tool 262III. TEE Imaging of the Thoracic Aorta andAortic Arch Vessels 263A. Ascending Aorta 263B. Descending Aorta 263C. Aortic Arch 264IV. Epiaortic Scanning 265V. Aortic Atherosclerosis 266A. Aortic Atherosclerosis and OutcomesAfter Cardiac Surgery 266B. Sensitivity and Specificity ofIntraoperative Techniques forAssessment of Aortic Atheromatosis:TEE, Epiaortic Scan, ClinicalPalpation 270C. Related Echocardiographic Findingswith Aortic Atherosclerosis 270VI. Aortic Dilatation and Aneurysms 270A. TEE as a Diagnostic Tool for ThoracicAortic Aneurysms 271B. Sinus of Valsalva Aneurysms 271VII. Aortic Dissection 272A. Clinical Background 272B. Classification of Aortic Dissection 274C. Imaging Modalities and DiagnosticAccuracy in Aortic Dissection 276D. Associated Complications 277E. Aortic Intramural Hematoma 278VIII. Traumatic Rupture of Aorta 279IX. Surgical Strategy in the Management of theAtherosclerotic Ascending Aorta 280References 282I. ANATOMICAL CONSIDERATIONSThe aortic wall is composed of three layers: the intima, themedia, and the adventitia. The intima is a delicate endotheliallayer. The media is a layer composed mainly ofelastic fibers arranged in a spiral manner; it contains relativelylittle smooth muscle and collagen between theelastic fibers. The adventitia, the outer layer of the aorticwall, is composed predominantly of elastic tissue, collagen,and the vasa vasorum. The elastic tissue is responsiblefor the distensibility (elastic recoil) of the aorta (Ao)while the collagen is the main determinant of the tensilestrength. The vasa vasorum provides blood flow to theouter half of the aortic wall including much of the media.The Ao is divided anatomically into thoracic andabdominal components. The thoracic Ao is further subdividedinto ascending, transverse (arch) and descendingsegments. The ascending Ao is 5 cm in length. It isdivided into the proximal aortic root and a more distaltubular portion which joins the aortic arch. The aorticroot extends from the aortic valve (AoV) to the sinotubularjunction and contains the sinuses of Valsalva which bulge261