Cardiovascular Pathology I Flashcards
What are the six pathological mechanisms of heart failure?
1. Failure of the pump
2. Obstruction to flow
3. Regurgitant flow
4. Shunted flow
5. Disorders of cardiac conduction
6. Rupture of the heart of major vessel
What are three diseases of arteries?
Atherosclerosis, hypertension, and aneurysm
What are three diseases of veins?
Varicose veins, thrombophlebitis, and phlebothrombosis
What causes atherosclerosis?
Build-up of fatty plaques, cholesterol, cellular waste products, calcium, fibrin, etc., in artery walls -> artery becomes thick and less elastic.
What is an artheroma?
A fibro-fatty plaque found in atherosclerosis
What part of the artery does atherosclerosis affect?
Imtima
What can atherosclerosis lead to?
Myocardial infarction, ischemic heart disease, stroke, aortic aneurysm, leg gangrene
What is a fatty streak?
First sign of atherosclerosis, consists of lipid-containing foam cells
Describe the pathogenesis of atherosclerosis
1. Injury to epithelium, formation of fatty streaks
2. Monocytes attach to tissue and differentiate into macrophages, which engulf lipids and form foam cells
3. Cytokines released by macrophages cause smooth muscle to migrate into intima and change from contractile to repair phenotype
4. Fibrous cap of smooth muscle and matrix forms above plaque, which is made up of foam cells, cholesterol, necrotic cells and cell debris
5. Advanced atherosclerosis: fibrous cap degradation and smooth muscle death
6. Unstable coronary artery disease: rupture of plaque leading to aggregation of platelets and formation of thrombus, causing narrowing of lumen, possible embolism and myocardial infarction or stroke
What is the composition of an atheromatous plaque?
Inner is necrotic centre made up of cell debris, cholesterol crystals, foam cells, calcium
Fibrous cap that covers the plaque is made up of smooth muscle cells, macrophages, foam cells, collagen, elastin, proteoglycans, neovascularisation
What are non-modifiable risk factors for developing atherosclerosis?
Age (middle to late), sex (male>female), genetic (hyperchol., hyperlipidemia) family history
What are modifiable risk factors for developing atherosclerosis?
Hyperlipidemia (HDL/LDL ratio), hypertension, smoking, diabetes, lifestyle (diet, exercise, stress, obesity)
What is considered hypertension?
Sustained diastolic pressure of >90mmHg or sustained systolic pressure of >140mmHg
What complications may arise from hypertension?
Organ damage to kidneys, heart and brain
What is essential hypertension?
Also called primary hypertension, when no single cause determinable
What is secondary hypertension?
Clearly identifiable cause is determined
What can cause secondary hypertension?
Primary renal disease, endocrine tumours, cardiovascular disease, neurologic issues
What systemic changes can be found in an individual with hypertension?
Left ventricular hypertrophy, heat failure (eventually), arrhythmias, severe atherosclerosis, renal disease, stroke, attic wall dissection
What is cor pulmonale?
Failure of the right side of the heart, caused by pulmonary hypertension secondary to intrinsic pulmonary disease
How does acute pulmonary hypertension present?
Dilated right ventricle
How does chronic pulmonary hypertension present?
Hypertrophy of right ventricle, emphysema, scarring of lung tissue, chronic embolisation
What can hypertension result in?
Accelerated atherogenesis, degeneration of large and medium artery walls leading to increased risk of aortic dissection and cerebrovascular haemorrhage, damage to media of arterioles, end organ damage (heart, kidneys, eyes, brain)
What is an aneurysm?
Abnormal dilation of blood vessel or wall of the heart