Pathology of Atherosclerosis and Hypertension

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Questions and Answers

What is the main characteristic of Monckeberg medial calcific sclerosis?

It is a form of atherosclerosis.

It occurs primarily in patients under 50 years old.

It involves occlusion of arterial lumens.

It is characterized by calcific deposits in the walls of muscular arteries. (correct)

Which of the following is a major unmodifiable risk factor for atherosclerosis?

Age (correct)

Obesity

Hypertension

Smoking

Which type of artery is primarily associated with atherosclerosis?

Arterioles

Medium-sized muscular arteries (correct)

Small arteries

Large elastic arteries

What is true about arteriovenous fistula?

It is a type of vascular anomaly. Signup and view all the answers

What is the main pathological feature of atherosclerosis?

Intimal lesions known as atheromas. Signup and view all the answers

What is the primary composition of a false aneurysm?

Both hematoma and fibrous tissues Signup and view all the answers

Which of the following conditions is a form of arteriolosclerosis?

Hyaline arteriolosclerosis Signup and view all the answers

Which of the following is NOT a recognized cause of aneurysm?

Aortic dissection Signup and view all the answers

Which risk factor is considered modifiable in relation to atherosclerosis?

Hyperlipidemia Signup and view all the answers

Which statement accurately describes the response to injury hypothesis related to atherosclerosis?

It emphasizes chronic endothelial injury as a key factor. Signup and view all the answers

What is the primary condition often associated with malignant hypertension?

Renal failure Signup and view all the answers

Which type of hypertension constitutes the vast majority of hypertension cases?

Essential (idiopathic) hypertension Signup and view all the answers

In the context of aortic dissection, what is a common etiology?

Marfan syndrome Signup and view all the answers

Which of the following mechanisms does NOT initiate noninfectious vasculitis?

T-cell activation Signup and view all the answers

What is the distinguishing feature of malignant hypertension?

Blood pressure consistently over 200/120 mmHg Signup and view all the answers

What is considered the primary abnormality in patients with hypertension?

Systolic pressure exceeding 140 mmHg Signup and view all the answers

What characterizes the first stage of atherosclerosis?

Intimal thickening and accumulation of foam cells Signup and view all the answers

Which component is NOT part of an atheromatous plaque?

Smooth muscle cell layer Signup and view all the answers

What can result from plaque rupture in atherosclerosis?

Hemorrhage into the plaques Signup and view all the answers

Which complication is associated with atherosclerosis affecting the aorta?

True aneurysm Signup and view all the answers

What term describes the localized abnormal dilatation of a blood vessel?

Aneurysm Signup and view all the answers

What is a characteristic of advanced atheromatous lesions?

They diffusely involve the arterial wall. Signup and view all the answers

Which factor is NOT typically associated with atherosclerosis?

Low unsaturated fat consumption Signup and view all the answers

What process describes the discharge of plaque debris into the bloodstream?

Atheroembolism Signup and view all the answers

What is the primary site affected by giant cell arteritis?

Arteries in the head, especially the temporal arteries Signup and view all the answers

Which of the following symptoms is commonly associated with giant cell arteritis?

Sudden and permanent blindness Signup and view all the answers

Which type of vessel is primarily affected in polyarteritis nodosa?

Medium-sized muscular arteries Signup and view all the answers

Which of the following is a characteristic feature of Wegener's granulomatosis?

Acute necrotizing granulomas in the respiratory tract Signup and view all the answers

What is a common demographic associated with thromboangiitis obliterans (Buerger disease)?

Males before the age of 35 years who are heavy smokers Signup and view all the answers

Which of the following is NOT typically involved in polyarteritis nodosa?

Pulmonary circulation Signup and view all the answers

What type of inflammation characterizes giant cell arteritis?

Granulomatous inflammation Signup and view all the answers

What pathological changes are associated with Wegener's granulomatosis?

Focal necrotizing glomerulonephritis Signup and view all the answers

Which HLA haplotypes have been associated with increased prevalence in certain patients?

HLA-A9 and HLA-B5 Signup and view all the answers

What is a key characteristic of Raynaud phenomenon?

Paroxysmal pallor or cyanosis of digits Signup and view all the answers

Which condition is NOT commonly associated with Secondary Raynaud phenomenon?

Varicose veins Signup and view all the answers

What population trend is observed regarding the incidence of varicose veins?

Higher prevalence in women due to pregnancy Signup and view all the answers

Which tumor type is categorized as a highly malignant vascular tumor?

Angiosarcoma Signup and view all the answers

What is a common risk factor for developing varicose veins?

Sedentary lifestyle Signup and view all the answers

What is the most common demographic for lower extremity varicose veins?

Adult females during pregnancy Signup and view all the answers

What condition is indicated by the term 'paroxysmal pallor'?

Raynaud phenomenon Signup and view all the answers

Study Notes

Arteries Classification

Arteries are categorized by size and structure
Large arteries (elastic arteries): Examples include the aorta and its branches.
Medium-sized arteries (muscular arteries): Examples are coronary and renal arteries.
Small arteries (less than 2mm in diameter) and Arterioles (20 to 100 microns).

Structure of a Normal Artery

Endothelium: The inner lining.
Internal elastic lamina: A layer of elastic tissue beneath the endothelium.
Media: The middle layer, composed primarily of smooth muscle cells and elastic fibers.
External elastic lamina: An elastic tissue layer found below the media.
Adventia: The outermost layer, composed mainly of connective tissue.

Arteries vs. Veins vs. Capillaries

Artery: Thick walls, carry blood away from the heart.
Vein: Thin walls, carry blood towards the heart.
Capillary: Single layer of endothelial cells, site of exchange between blood and tissues.

Vascular Anomalies

Berry aneurysm: A congenital defect in the media of vessels of the Circle of Willis.
Arteriovenous fistula: An abnormal connection between an artery and a vein, often causing a visible mass.

Arteriosclerosis

Thickening and loss of elasticity of arterial walls.
Includes three forms:
- Atherosclerosis: The most frequent and important type.
- Monckeberg medial calcific sclerosis: Calcific deposits in muscular arteries of people over 50.
- Arteriolosclerosis: A disease of small arteries and arterioles, seen commonly in elderly people with hypertension and diabetes mellitus.

Atherosclerosis (ATH)

Characterized by intimal lesions (atheromas or atheromatous plaques).
These lesions protrude into the lumen, possibly obstructing blood flow.
A high contributor (over 50%) to deaths resulting from ischemic heart disease or cerebrovascular accidents.
Response to injury hypothesis is the most widely accepted theory regarding the development of ATH.
Chronic endothelial injury is often the trigger for ATH.

Risk Factors of Atherosclerosis

Unmodifiable risk factors:
- Age.
- Male gender. (Women are generally protected by estrogen).
- Familial Predisposition (likely polygenic).
- Genetic factors, including lipoprotein abnormalities (like familial hypercholesterolemia).
Modifiable risk factors:
- Hyperlipidemia.
- Hypertension.
- Smoking.
- Diabetes mellitus.
Lesser risk factors: (non-quantifiable but still important)
- Obesity.
- Physical inactivity.
- Stressful lifestyle.
- High carbohydrate intake.
- Post-menopausal estrogen deficiency.
- Unsaturated fat intake.
- Chlamydia pneumoniae infection.

Clinical Significance of Atherosclerosis

Small arteries: Atheroma occlusion can lead to ischemia due to thrombosis.
Large and medium-sized arteries: Atheromatous plaques can weaken vessel walls and contribute to aneurysm formation.

Morphology of Atherosclerosis

Fatty streaks: Intimal thickening and lipid accumulation from foam cells, but do not significantly obstruct blood flow.
Atheromatous Plaques: Raised lesions composed of a fibrous cap and lipid core, significantly impacting blood flow.
Advanced atheromatous lesions: Progress to become diffusely involved in arterial wall.
Different degrees of atherosclerosis can exist in the aorta.

Complications of Atherosclerosis

Focal rupture, ulceration, erosion, and superadded thrombosis.
Hemorrhage into the plaques, sometimes forming a hematoma, often observed in coronary arteries
Atheroembolism: Plaque rupture releases debris into the bloodstream, resulting in microemboli composed of plaque contents.
Aneurysmal dilatation: Atherosclerosis-induced aortic aneurysm.

Aneurysms

A localized abnormal dilatation of a blood vessel (or heart).
Types:
- True aneurysm (involves all three layers).
- False aneurysm (wall consists of hematoma or fibrous tissues).
Causes:
- Atherosclerosis.
- Cystic medial degeneration of arterial media.
- Trauma.
- Congenital defects.
- Infections (mycotic aneurysm).
- Syphilis.

Aortic Dissection

Dissection of blood between (and along) the laminar planes within the aorta media.
Forms blood-filled channels within the aortic wall.
Possible causes:
- Primarily unknown.
- Hypertension.
- Marfan syndrome.
- Complications of arterial cannulation or catheterization (iatrogenic).
- Sometimes occurring during or after pregnancy.

Hypertensive Vascular Diseases (Hypertension)

High blood pressure over time (sustained diastolic pressure over 90mmHg or sustained systolic blood pressure over 140mmHg).
Types:
- Idiopathic (essential): Making up 95% of cases, often benign but sometimes malignant.
- Secondary: 5% of cases, caused by various factors.
Causes of Secondary Hypertension: Renal causes, endocrine causes, cardiovascular causes, and neurologic causes.

Inflammatory Diseases of Blood Vessels (Vasculitides)

Infectious Vasculitis: Infection-induced inflammation.
Immune-mediated Vasculitis: Immunological mechanisms trigger inflammation (immune complex deposition, antineutrophil cytoplasmic antibodies (ANCAs), anti-endothelial cell antibodies).
Vasculitides associated with other disorders: Rheumatoid arthritis, SLE, inflammatory bowel diseases.

Giant Cell (Temporal) Arteritis

Chronic granulomatous inflammation of large to medium-sized arteries, often the temporal arteries, but can also affect vertebral and ophthalmic arteries.
Primarily affects older individuals.
Symptoms include: facial pain/headache (especially along the temporal artery), fever, fatigue, and weight loss.
High Erythrocyte Sedimentation Rate (ESR).

Polyarteritis Nodosa (PAN)

Systemic vasculitis of small or medium-sized muscular arteries, often affecting renal and visceral vessels but sparing the pulmonary circulation.

Wegener Granulomatosis

Necrotizing vasculitis characterized by:
- Granulomas in the upper respiratory tract (nose, sinuses, throat and lungs).
- Necrotizing or granulomatous vasculitis in small and medium-sized vessels (especially in the lungs and upper airways).
- Renal disease with focal necrotizing and often crescentic glomerulonephritis.

Thromboangiitis Obliterans (Buerger Disease)

Segmental, acute and chronic inflammation of medium and small arteries.
Primarily affects the tibial and radial arteries.
Most commonly seen in young male smokers.
Pathogenesis is suspected to involve:
- Direct endothelial toxicity from tobacco or Tobacco hypersensitivity.
- Anti-endothelial cell antibodies.
- Influence of MHC haplotypes (HLA-A9 and HLA-B5).
- Genetic factors (seen more commonly in specific ethnic groups)

Raynaud Phenomena

Exaggerated vasoconstriction of digital arteries and arterioles.
Characteristic color changes in the fingers resulting from periods of pallor, cyanosis, and redness related to blood flow to the fingers.
Can be a primary disease entity (Raynaud's disease) or secondary to other conditions (SLE, scleroderma, Buerger disease, atherosclerosis).

Varicose Veins

Abnormally dilated and tortuous veins due to prolonged intraluminal pressure and loss of vessel wall support.
Commonly affecting veins in the upper and lower leg.
Predisposing factors include obesity and pregnancy.
Genetic and familial tendencies.

Tumors of the Vascular System

Tumors of blood vessels and lymphatics range from benign hemangiomas through intermediate lesions (Kaposi's sarcoma and haemangioendothelioma) to malignant angiosarcomas.
Some tumors originate in the endothelial cells (hemangioma, lymphangioma, or angiosarcoma).
Others originate in cells supporting the blood vessels (glomus tumors or hemangiopericytomas).
Primary tumors of large vessels (aorta, pulmonary artery and vena cava) are mostly connective tissue sarcomas.

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Description

Test your knowledge on the characteristics and risk factors associated with atherosclerosis, hypertension, and related vascular conditions. This quiz covers key concepts, pathological features, and classifications within cardiovascular pathology.