IM DISEASES OF THE AORTA Page 4 of 4

DISEASES OF THE AORTADr. Allan B. Ruales080709Aorta

Normal = 3cm origin, 2.5cm

Aortic aneurysm

Atherosclerosis

Cystic medial necrosis

TB

Syphilitic infection

Mycotic infection

Rheumatic aortitis

Trauma

Aortic dissection

Cystic medial necrosis

Systemic hypertension

Atherosclerosis

Takyasus arteritis

Giant cell arteritis

*usually if with aneurysm, prone to dissectAortic occlusion Atherosclerosis

Throboembolism

Aortitis

Syphilitic aortitis, rheumatic aortitis

Takyasus arteritis

Giant cell

AORTIC ANEURYSM

Pathologic dilatation of a segment of the aorta

True: involves 3 layers (intima, tuinica media, adventitia)

Pseudoaneurysm: intima and medial layers

Dilatation lined by adventitia

Gross appearance

Fusiform: entire circumference (diffusely dilated)

Saccular: portion of the circumference (outpouching of vessel wall)

MC cause: atherosclerosis

CYSTIC MEDIAN NECROSIS

Degeneration of collagen and elastic fibers in the tunica media with loss of medial cells replaced by mucoid material

Proximal aorta

Prevalent with Marfan and Ehlers-Danlos syndrome

Familial clustering 20%

Syphilis

Uncommon

90% ascending aorta or arch

Tuberculous typically affect the thoracic aorta from direct extension of infection from hilar LN or contiguous abscesses

Mycotic

Rare resulting from infection o an atherosclerotic plaque

Usually saccular

Vasculitides

Arch and descending thoracic aorta

Takayasus and giant cell arteritis

Spondyloarthropathies

Ascending aorta

Behcets thoracic aneurysm

Trauma

Penetrating or non-penetrating

Descending thoracic beyond site of insertion of ligamentum arteriosum

Congenital

Assoc with anomalies like bicuspid aortic valve

THORACIC AORTIC ANEURYSM

Clinical manifestation and natural hx depend on location

Mc etiology: cystic medal necrosis

Arch and descending aorta

Ave growth rate: 0.1 to 0.4cm per year

Risk of rupture related to site and presence of symptoms

Inc for ascending >6cm and descending >7cm

Symptoms are from compression of erosion of adjacent tissue

Recurrent laryngeal nerve: hoarseness

May cause CHF as a consequence of AR

Compression of SVC = superior vena caval syndrome Xray: widening of mediastinal shadow and displacement or compression of trachea or left mainstem bronchus

2D echo: assess prox ascending and descending thoracic aorta

CT and MRI: for thoracic aorta

Asymptomatic patients with aneurysms too small for surgery, performed 6-12months to monitor expansion

Aortography: length and involvement of branch vessels

Treatment: long term beta blocker therapy

Control HPN

Operative repair: placement of prosthetic graft, asymptomatic > 5cm

ABDOMINAL AORTIC ANEURYSM

More seen in males Increase incidence with age

90% >4cm have atherosclerosis usually below level of renal arteries

Risk of rupture increases with size

>5cm 20-40%

1.0 normal