Intimal flap and tear in a patient with acute type A aortic dissection. (A) In the transoesophageal echocardiography short-axis view, a mobile linear flap is seen in the aortic root, just above the aortic valve leaflets (which can also be seen). The tear in the flap, where the small central true lumen communicates with the false lumen, is shown by the white arrow. (B) In the same patient, a 26-year-old man with no other co-morbidities, a short-axis view just below the origin of the flap, showing a bicuspid aortic valve.
Visualization of the left coronary ostium. Transoesophageal echocardiography short-axis view: in the left panel, a small true lumen is seen, from which the left coronary artery (asterisk) arises. Separate origins of the left anterior descending and circumflex branches can be seen—this was invaluable information for the cardiac surgeon. In the right panel, colour flow mapping shows unobstructed flow from true lumen into the left coronary branches.
Visualization of the head and neck vessels. Off-axis transoesophageal echocardiography view of the aortic arch. (A) A linear dissection flap is seen. The origins of the left common carotid and subclavian arteries as seen to arise from the smaller, true lumen (white arrows). (B) In the right panel, colour flow mapping shows unobstructed flow from true lumen into the head and neck vessels.
Intramural haematoma. In the transoesophageal echocardiography short-axis view, a cross-section of the aortic root is shown. The aortic wall is markedly thickened (white arrowheads). The intima has areas of focal echo brightness, characteristic of atherosclerosis—this is one method of distinguishing IMH from thrombus within the lumen of aortic aneurysm. There is an area of echo lucency within the haematoma, but no dissection flap or false lumen is seen. An echo free rim is seen around the aorta, suggestive of free blood.
Transesophageal echocardiogram (horizontal, 0-degree view) of an aortic arch with large, multi-lobed, ulcerated protruding atheromas (arrows).
Diseases of the aorta
30thApril 2010Dr. Fateh Ali Tipoo SultanFCPS (Med), FCPS (Card)Diplomate Certification Board of Cardiac CTCertification National Board of EchocardiographyAssistant Professor &Consultant CardiologistAga Khan University HospitalDiseases of the Aorta
Aortic Dissection• Deterioration of medial collagen and elastin• A tear in the intimal layer allows blood toenter the intima-media space• Blood then propagates down this new spacecreating a “true” and a “false” lumen3
Factors Predisposing to Dissection• Hypertension• Marfan and Ehler-Danlos• Coarctation and bicuspid aortic valve• Pregnancy• Trauma• Perforation through an intimal atheromatousplaque4
Intimal flap and tear in a patient with acute type A aortic dissectionMeredith E L , Masani N D Eur JEchocardiogr 2009;10:i31-i39
Predicting death in Patients withAcute Type A Aortic Dissection• 547 pts; IRAD; Jan 96-Dec 99• In hospital mortality 32.5%• Age > 70 years• Abrupt onset of chest pain• Hypotension, Shock, Tamponade• Kidney failure• Pulse deficit• ECG abnormalities8Circulation 2002
Clinical Presentation• Pain 85-96%Sudden 85%Severe 90%Tearing/Ripping 50%• SyncopePain, obstruction, barroreceptors• NeurologicalCVA 5%Paraparesis or paraplegia• CHF 7%• MI rare9
TEE in Aortic Dissection: PitfallsTrue Dissection Flap Artifacts, ReverberationsDistinct, well-visualized Vague, blurryUndulates with cardiac cycle Crosses true anatomic barriersPresent in multiple views Does not demonstrate typicalundulation patternSeparates true from false lumen Does not separate true from false23
Intramural Hematoma: Diagnosis• Contained hemorrhage within the mediallayer of the aortic wall• Crescentic area along the aortic wall• Prevalence 10-15% in CT/MRI/TEE• Normal size lumen• False negative aortograms38
Atypical Aortic Dissection: IHEcho Features• Localized thickening of Ao wall– Usually crescentic– Occasionally circumferential– Echo-lucent spaces common• Relatively smooth luminal surface• Absence of dissection flap• Maintenance of circular lumen41
Intramural haematoma.Meredith E L , Masani N D Eur JEchocardiogr 2009;10:i31-i39
Intramural Hematoma of the AortaPredictors of Progression to Dissection and Rupture– Location in the ascending aorta– Initial hematoma thickness > 11mm– Moderately ectatic aortic diameter with progression43Circulation 2002Circulation 2003
Penetrating Atherosclerotic Ulcer• Almost exclusively in the descending Ao• Usually remains localized• Elderly HTN, evidence for otheratherosclerotic CV disease• Chest and back pain without associated ARor neurological deficits44
Penetrating Atherosclerotic Ulcer• Natural history is unclear• No defined strategy• Surgical repair for– Pseudoaneurysm– Transmural rupture– Continued pain– Distal embolization– Aneurysmal dilatation47
Aortic aneurysm• Definition: pathological dilatation of the normalaortic lumen involving one or several segments• Fusiform (common), saccular• Pseudoaneurysm: well-defined collection ofblood and connective tissue outside the vessel wall
Aortic Atherosclerosis• Atheroma• Protruding Atheroma• Complex plaque– 4mm or more thick and/or mobile component53
• Atherosclerotic lesions of the aorta detectedby TEE have been recognized as animportant cause of stroke and peripheralembolic disease• Using TEE the prevalence of thoracic aorticatheromas is 27% in patients who haveexperienced a previous embolic event• When atheromas are present the incidenceof stroke is 12% in one yearN Eng J Med 1996;334:1216-21N Eng J Med 1994;331:1474-9J Am Coll Cardiol 2000;35:545-54
• Plaque thickness and plaque composition asassessed by TEE have been identified asmajor risk factors for emboliccomplications• A strong association has been demonstratedbetween protruding non-calcified plaques>4mm in the aorta detected by TEE and therisk of ischemic stroke and peripheralembolismN Eng J Med 1994;331:1474-9Circulation 1997;96:3838-41
• Atheromas in the aortic arch and ascendingor descending aorta identified by TEE maybe the cause of many otherwise unexplainedstrokes• Role of Statins, ACEI, Anticoagulants andAntiplatelet agents uncertain
Trans-esophageal echocardiogram (horizontal, 0-degree view) of an aorticarch with large, multi-lobed, ulcerated protruding atheromas (arrows).Kronzon I , Tunick P A Ann Intern Med1997;126:629-637
Coarctation of AortaPathophysiology• Narrowed aorta produces increased leftventricular afterload and wall stress, leftventricular hypertrophy, and congestiveheart failure• Systemic perfusion is dependent on theductal flow and collateralization in severecoarctation
Coarctation of AortaIndications for operation1. Reduction of luminal diameter greaterthan 50% at any age2. Upper body hypertension over 150mmHgin young infant ( not in heart failure )3. CoA with congestive heart failureat any age
Blunt Aortic-Brachiocephalic Trauma66Fisher et al, 1981(n=510)Vignon et al, 1998(n=25)Aorticisthmusmainlyinvolved