Blood vessels (Condensed) 2026

Arteriolosclerosis associated with a thickened arterial wall with homogenous pink, hyaline material; due to hypertension and DM

Hyaline arteriolosclerosis

Type of arteriolosclerosis with onion-skin lesion (concentric, laminated thickening composed of smooth muscle cells with thickened basement membrane); effect of severe hypertension

Hyperplastic arteriolosclerosis

Cause of necrotizing arteriolitis (hyperplastic arteriolosclerosis + fibrinoid deposits and vessel wall necrosis)

Malignant hypertension

Initiating event for the development of atherosclerosis

Endothelial dysfunction - Causes include hemodynamic disturbances and hypercholesterolemia

Most common sites of involvement in atherosclerosis

Lower abdominal aorta and iliac arteries > Coronary arteries > Popliteal arteries > Internal carotid arteries > Circle of Willis

Percentage of stenosis at which ischemia starts in atherosclerotic vessels (critical stenosis)

70-75%

Bacterial infection associated with obliterative endarteritis of the vasa vasorum, causing aneurysms

Tertiary syphilis (Syphilitic aortitis)

Why are intracranial arteries more prone to aneurysm formation?

Absence of external elastic lamina

Most common site of abdominal aortic aneurysms (2)

Between the renal arteries, Bifurcation of the aorta. AAAs usually arise at infrarenal aorta since there are fewer elastic fibers and collagen, with more fragile vasa vasorum, leading to lesser oxygenation of the media in that segment.

Condition where blood tunnels through layers of the vessel wall through an intimal tear; sudden knife-like anterior chest pain radiating to back

Aortic dissection

Most common site of aortic dissection

Ascending aorta within 10 cm of the aortic valve

Large vessel vasculitis that causes headache, pain/tenderness along superficial temporal artery + diplopia; (+) granulomatous inflammation with T cells and multinucleated giant cells

Giant cell arteritis

Large vessel vasculitis in <50 y.o., occurring at the aortic arch, producing weakening of the pulses in the upper limbs, and ocular disturbances

Takayasu arteritis

Commonly affected large vessel in Takayasu arteritis

Aorta

Infection associated with polyarteritis nodosa

Hepatitis B

Small vessel, immune complex mediated vasculitis; associated with MPO-ANCA, leukocytoclasia

Microscopic polyangiitis (hypersensitivity vasculitis)

Conditions associated with eosinophilic granulomatosis with polyangiitis (EGPA) (2)

Asthma and allergic rhinitis

Classic triad of EGPA

Asthma, Eosinophilia, Vasculitis

Small vessel, T-cell mediated vasculitis associated with PR3-ANCA

Granulomatosis with polyangiitis (GPA)

Small vessel vasculitis associated with upper airway involvement, acute necrotizing granulomas in the respiratory tract, and FSGS/crescentic glomerulonephritis

Granulomatosis with polyangiitis (Wegener granulomatosis). This can lead to persistent pneumonitis, chronic sinusitis, and renal disease.

Small vessel vasculitis heavily associated with smoking, Raynaud phenomenon, instep claudication, and a thrombus with microabscesses; highly associated with smoking

Thromboangiitis obliterans (Buerger disease)

Exaggerated vasoconstriction in response to cold or emotion, affecting the extremities

Raynaud phenomenon

Pattern of color changes that occur in the extremities in Raynaud phenomenon

Red → White → Blue (Proximal vasodilation → central vasoconstriction → distal cyanosis)

Illicit drug associated with myocardial vessel vasospasms

Cocaine

Type of dermatitis caused by varicose veins; due to chronic venous insufficiency

Stasis dermatitis

Two most common causes of superior vena cava syndrome

Lung carcinoma, Mediastinal lymphoma

Most common etiology of lymphangitis

Group A β hemolytic Streptococci (GABHS)

Most common vascular ectasia (birthmark); most cases spontaneously regress

Nevus flammeus

Type of nevus flammeus that grows during childhood and persists over time

Port wine stain

Disease associated with port wine stain, seizures, ipsilateral venous angiomas in the cortical leptomeninges, intellectual disability; due to GNAQ mutations

Sturge Weber syndrome; AKA Encephalotrigeminal angiomatosis

Pattern of distribution of the port wine stain in Sturge Weber syndrome

Trigeminal nerve distribution

Hormonal state associated with the development of spider telangiectasias

Hyperestrogenic state

Hereditary hemorrhagic telangiectasia; associated with TGF-β mutations; autosomal dominant transmission

Osler-Weber-Rendu disease. Complications include rupture and bleeding.

Juvenile hemangioma, common in newborns, present at birth, rapidly growing for few months but completely regresses in age 7 in most cases

Strawberry hemangioma

Lobular capillary hemangioma, common in the gingiva of pregnant women; associated with a history of trauma

Pyogenic granuloma

Hemangiomas occurring in the deep structures (liver in 1/3); does not spontaneously regress; non-encapsulated, potentially causing intravascular thrombosis

Cavernous hemangiomas

Disease presenting with angiomas, hemangioblastomas, paragangliomas, pheochromocytomas, clear cell renal cell carcinomas, pancreatic serous cystadenomas, and endolymphatic sac tumors

Von-Hippel Lindau Disease (VHL)

Genetic condition associated with cavernous lymphangiomas (cystic hygroma)

Turner syndrome

Malignant vascular neoplasm derived from endothelial cells; occurring mostly in the elderly (peak: 7th decade of life)

Angiosarcoma