Aneurysm, Dissection

Aneurysm Aneurysm: localized dilation of the vessels or the heart May occur at any site, most important is aorta and ventricles. True aneurysm is bounded by vessel wall False aneurysm: extravascular hematoma with communication to vascular space (Pulsating hematoma)

Aneurysm Congenital or acquired Aortic aneurysm: –Causes: Atherosclerosis Cystic medial degeneration Others: trauma, congenital (berry aneurysm), infections (mycotic aneurysm, syphilis), Vasculitis

Aneurysm Mycotic aneurysm (infection) –Route of infections Embolization of infections Extension of adjacent infection Circulating organisms

Aneurysm Saccular aneurysm: localized bulging of vessel Fusiform aneurysm: long segment of the vessel is involved.

Aortic Aneurysm Atherosclerosis is the most common cause Common in abdominal aorta: Abdominal Aortic Aneurysm (AAA) May occur at other sites: thoracic aorta, common iliac artery…. AAA is usually below the level of renal arteries and above aortic bifurcation

Aortic Aneurysm AAA can be saccular or fusiform –Atherosclerosis – weak media – aneurysm – thrombosis. –Mycotic AAA: atherosclerosis with infection, bacteria: Salmonella

Aortic Aneurysm Pathogenesis: Genetic Predisposition >50 years M>F Marfan syndrome Genetic defects in structural proteins Atherosclerosis

Aortic Aneurysm Complications: –Rupture with massive hemorrhage 2% in <4 cm aneurysm 5-10% in >5 cm aneurysm –Occlusion of vessels: renal artery, mesenteric, iliac –Embolism –Compression of other structures: eg. ureters

Aortic Aneurysm Presentation of AAA: –Abdominal mass: pulsating –Any of the complications

Aortic Aneurysm Presentation of Thoracic aneurysm –Respiratory difficulties –Difficulty in swallowing –Cough –Chest pain –Heart disease: valvular disease, Ischemic heart disease Syphilitic aneurysm

Aortic Dissection

Dissection is hematoma within the vessel wall with dissection of blood between layers of the media (muscle layer) Can rupture resulting in massive hemorrhage

Aortic Dissection Two groups of patients: –Men years with hypertension –Young with connective tissue disorder eg. Marfan syndrome –Others: iatrogenic, Pregnancy –Dissection is unusual in severe atherosclerosis

Aortic Dissection How does is happen? –Intimal tear usually within 10 cm of the aortic valve –Dissection of blood into aortic wall –Dissection can extend proximally or distally usually between the middle and outer third of the muscle layer –Dissection can rupture outside the vessel –Or can open inside to the vascular space resulting in Chronic dissection

Aortic Dissection Pathology: –Cystic medial degeneration Degeneration of the muscle Deposition of plasma proteins and collagen Fragmentation of elastic fibers

Aortic Dissection Types: –Type A: Common, dangerous Proximal Ascending aorta: DeBakey type I Ascending and Descending thoracic aorta: DeBakey type II –Type B: Distal to subclavian artery DeBakey type III

Aortic Dissection Presentation: –Sudden Severe pain: anterior chest radiating to the back then moving downward Complications: –Rupture –Cardiac tamponade –Occlusion of vessels: coronary, mesenteric, renal….

Berry Aneurysm

Arteriovenous Fistula Communication between arterial and venous circulation Causes: –Developmental –Trauma/repair –Rupture of vessels –Aneurysm –Inflammatory process –surgical

Arteriovenous Fistula If small: not significant If large can cause heart failure May rupture resulting in hemorrhage

Varicose Veins

Abnormal dilated, tortuous veins Due to prolonged increase in pressure Common in superficial veins of legs Occupational relation: Long stand, long automobile and airplane rides Common: 15-20% of general population More in >50 years, obese women Familial tendency

Varicose Veins Valve deformity, thrombosis Pathology: Thickening and thinning of the vessel walls, degeneration, calcification, muscle hypertrophy (Phlebosclerosis)

Varicose Veins Presentation: –Venous stasis, congestion, edema, pain, thrombosis –Skin atrophy, ulcers, poor healing Esophageal varices Hemorrhoides

Thrombophlebitis and Phlebothrombosis Thrombophlebitis is venous thrombosis Phebothrombosis is inflammation of veins Predisposing factors for thrombosis: –Heart failure, neoplasia, obesity, post operative, prolonged bed rest, genetic hypercoagulability

Thrombophlebitis and Phlebothrombosis Presentation: –DVT: edema, cyanosis, dilated superficial veins, tenderness, swelling, pain (Homan sign) –Others: veins in skull, dura, pelvic veins –Trousseau sign

Vascular Neoplasm

Benign Borderline Malignant

Hemangioma Common in infants, children Skin, mucosa, subcutaneous tissue Capillary hemangioma Cavernous hemangioma

Vascular Ectasia Nevous Flammeus: birth mark Spider Telangiectasia: in cirrhosis, pregnancy

Kaposi Sarcoma 1.Chronic: classic Old men, multiple red-purple skin plaques in lower extremities Slow growing 2.Endemic (African) KS Children in Africa Localized/generalized lymphadenopathy 3.Transplant-Associated KS 4.AIDS-Associated KS ¼ of AIDS patients, male, Homosexual

Kaposi Sarcoma Pathology –Patch –Plaque –Nodular Cause: associated with Human Herpes Virus type 8 (HHV8)

Angiosarcoma Malignant vascular neoplasm Sporadic Secondary: radiation, lymphedema Arise in any site: common in skin, soft tissue, breast, liver

Coarctation of Aorta