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Nonatheromatous Arteriosclerosis


George Thanassoulis

, MD, MSc, McGill University;

Haya Aziz

, MD, McGill University

Reviewed/Revised Apr 2022 | Modified Sep 2022
Topic Resources

Nonatheromatous arteriosclerosis is age-related fibrosis in the aorta and its major branches.

Arteriosclerosis is a general term for several disorders that cause thickening and loss of elasticity in the arterial wall.

Nonatheromatous forms of arteriosclerosis include

  • Arteriolosclerosis

  • Mönckeberg arteriosclerosis

Nonatheromatous arteriosclerosis causes intimal thickening and weakens and disrupts the elastic lamellae. The smooth muscle (media) layer atrophies, and the lumen of the affected artery widens (becomes ectatic), predisposing to aneurysm Overview of Aortic Aneurysms Aneurysms are abnormal dilations of arteries caused by weakening of the arterial wall. Common causes include hypertension, atherosclerosis, infection, trauma, systemic rheumatic diseases, and... read more Overview of Aortic Aneurysms or dissection Aortic Dissection Aortic dissection is the surging of blood through a tear in the aortic intima with separation of the intima and media and creation of a false lumen (channel). The intimal tear may be a primary... read more Aortic Dissection . Hypertension is a major factor in development of aortic arteriosclerosis and aneurysm. Intimal injury, ectasia, and ulceration may lead to thrombosis, embolism, or complete arterial occlusion.

Nonatheromatous arteriosclerosis is usually asymptomatic until complications (eg, aneurysm) develop. It may be incidentally detected during imaging tests done for unrelated reasons.


Hyaline arteriolosclerosis affects small arteries and arterioles in patients with diabetes; typically, hyaline thickening occurs, the arteriolar wall degenerates, and the lumen narrows, causing diffuse ischemia, especially in the kidneys.

Hyperplastic arteriolosclerosis occurs more often in patients with hypertension; typically, laminated, concentric thickening and luminal narrowing occur, sometimes with fibrinoid deposits and vessel wall necrosis (necrotizing arteriolitis). Hypertension Hypertension Hypertension is sustained elevation of resting systolic blood pressure (≥ 130 mm Hg), diastolic blood pressure (≥ 80 mm Hg), or both. Hypertension with no known cause (primary; formerly, essential... read more Hypertension promotes these changes, and arteriolosclerosis, by increasing arteriolar rigidity and increasing peripheral resistance, may help sustain the hypertension.

Mönckeberg arteriosclerosis

Mönckeberg arteriosclerosis (medial calcific sclerosis) affects patients > 50; age-related medial degeneration occurs with focal calcification and even bone formation within the arterial wall. Segments of the artery may become a rigid calcified tube without luminal narrowing. The diagnosis is usually obvious by plain x-ray. This disorder is clinically important only because it can greatly reduce arterial compressibility, causing extremely but falsely elevated blood pressure readings.

Key Points

  • Nonatheromatous arteriosclerosis causes thickening and loss of elasticity of the arterial wall in the absence of obvious atheromatous plaque.

  • There are two variants of nonatheromatous arteriosclerosis: arteriolosclerosis and Mönckeberg arteriosclerosis.

  • Diabetes, hypertension and age are risk factors for the development of nonatheromatous arteriosclerosis.

NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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