For each one of the forms of atheroma listed on the left select the most appropriate association from the list on the right. a. Atheromatous aneurysm. b. Complicated atheroma. c. Early atheromatous lesion. A. Affects vessels of less than 2 mm diameter. B. Fat in intimal smooth muscle cells. C. Mucoid degeneration of the media. D. Thinning of the media with loss of elasticity. E. Ulceration of the plaque with mural thrombus formation. The answer is D, E, B. Thinning of the media, with extension of plaque into it results in loss of elasticity and may allow an aneurysm to form; this usually occurs in the lower abdominal aorta. Plaques showing ulceration, thrombosis and calcification represent severe disease. Mucoid degeneration of the media (Erdheim’s medial degeneration) is associated with dissecting aneurysm which usually involves the proximal aorta (C). Atheroma usually affects vessels of more than 2 mm diameter (A).
Which ONE of the following is not a predisposing factor for atheroma? A. Cigarette smoking. B. High level of serum high density lipoprotein. C. High level of serum low density lipoprotein (LDL). D. Male sex. E. Systemic hypertension. The answer is B. High levels of serum HDL are associated with decreased risk of ischaemic heart disease; in vitro, HDL results in transfer of cholesterol from the intima of cultured aorta to the culture medium. High level of serum LDL is the major risk factor of atheroma (C); the others increase the risk by unknown mechanism.
For each of the types of systemic hypertension listed on the left select the most appropriate association from the list on the right. a. Accelerated phase hypertension. b. Chronic benign essential hypertension in a small vessel. c. Early benign essential hypertension. 28 A. Hyaline arteriolosclerosis. B. Hyaline arteriolosclerosis with fibrinoid necrosis. C. Hypertrophy of medial muscle and elastic. D. Medial calcification. E. Median and intimal necrosis of a segment of arterial wall. The answer is B, A, C. In accelerated phase (malignant phase) hypertension there is necrosis added to the features of benign hypertension, with permeation of the vessel wall by plasma and fibrin. Hyaline arteriolosclerosis is the lesion of chronic benign essential hypertension in a small vessel in which there is medial thickening plus intimal thickening which may narrow the lumen. The early feature of benign essential hypertension involve hypertrophy of medial muscle and elastic; larger vessels often dilate. Medial calcification (D) is dystrophic calcification of the larger vessels of the lower limbs in elderly people (Monckeberg’s sclerosis). Polyarteritis nodosa has the feature described in (E).
Which ONE of the following is not involved in the aetiology of systemic hypertension? A. Arteriolosclerosis. B. Chronic glomerulonephritis. C. Conn’s syndrome. D. Phaeochromocytoma. E. Raised sodium intake. The answer is A. Arteriolosclerosis is the result of hypertension. Renal hypertension is usually the result of chronic glomerulonephritis (B) or chronic pyelonephritis. Conn’s syndrome (primary hyperaldosteronism) is due to an adrenal tumour secreting aldosterone (C). Phaeochromocytomas (D) secrete catecholamines. Population studies have shown hypertension to correlate well with high average salt intake (E).
From the list of diseases on the left select the most appropriate histological description from the list on the right. a. Infiltration of aortic adventitia with plasma cells and lymphocytes. b. Periarteritis and endarteritis of the aortic vasa vasorum. 29 c. Thrombotic occlusion of short lengths of arteries and veins of limbs. A. Buerger’s disease. B. Giant cell (temporal) arteritis. C. Raynaud’s disease. D. Rheumatoid arteritis. E. Syphilitic aortitis. The answer is D, E, A. Lesions similar to those seen in the heart in rheumatic fever can be found in the walls of larger veins. The arteritic lesion of syphilis involves the whole vessel wall; damage to the vasa vasorum results in damage to the aortic media with aneurysm formation; this is usually in the thoracic aorta. Buerger’s disease (thromboangiitis obliterans) involves both arteries and veins. Giant cell (temporal) arteritis (B) occurs in the elderly; there is destruction of the elastic lamina with giant cell formation. Raynaud’s disease (C) is associated with abnormal spasm of digital vessels; the histological features are uncertain.