Systemic Hypertension Flashcards
What are the major classifications of hypertension?
Primary/essential or secondary
Benign or malignant
What is the most common form of hypertension?
Primary (no specific identifiable cause)
Benign more common
What is the difference between benign and malignant hypertension?
Benign: rises over years, never gets very high
Malignant: very high, may develop rapidly
What changes occur to arteries with ge?
Arteriosclerosis
Hyaline arteriosclerosis
What is arteriosclerosis?
Fragmentation of elastin, increased collagen and sometimes calcification in media of arteries (including aorta)
Increased collagen in intima
What changes occur in hyaline arteriosclerosis?
Deposition of plasma proteins in wall Increased collagen Smooth muscle atrophy Arteriole wall thickened by homogenous eosinophilic material (hyaline) Narrowed lumen
What kind of factors may contribute to risk of primary hypertension?
Polygenic genetic influences Lifestyle Age Gender Race
List 4 important classifications of causes of secondary hypertension
Renal
Endocrine
Vascular
Medications
What renal conditions can cause secondary hypertension?
Diabetic glomerulosclerosis
Polycystic renal disease
CRF
How does renal disease cause secondary hypertension?
Decreased capacity to excrete Na+
Excessive renin secretion in relation to volume
Excessive sympathetic activity
What endocrine conditions can cause secondary hypertension?
Phaeochromocytoma
Pituitary adenoma producing ACTH
Adrenocortical adenoma producing cortisol or aldosterone
What vascular conditions can cause secondary hypertension?
Renal artery stenosis
What medications can cause secondary hypertension?
GCS
High dose oestrogens
What other conditions can cause secondary hypertension?
Hypercalcaemia
OSA
When does atherosclerosis cause hypertension?
Only if in renal artery (rare; chronic ischaemia of kidney leads to excess RAAS secretion)
What kind of changes occur in essential hypertension?
Concentric LV hypertrophy Atherosclerosis in large and medium sized arteries Aortic dissection Berry aneurysm Hyaline arteriosclerosis
Where does hyaline arteriosclerosis occur?
In arterioles
What causes aortic aneurysm?
Weakening of the media, usually due to underlying atherosclerosis impinging on blood supply to the media
Where does blood collect in aortic dissection?
Media (tear occurs between intima and media)
What are 3 possible complications of aortic dissection?
Haemopericardium
Extension of dissection
Rupture
What causes most regional MIs?
Atherosclerosis with thrombosis in coronary artery
How can concentric hypertrophy of the LV cause HF?
Impairs diastolic filling
Increases myocardial O2 demand
Reduces coronary perfusion pressure gradient
What macroscopic changes are seen in the kidney in benign nephrosclerosis?
Thinned cortex
Granular appearance
What histological changes are seen in the kidney in benign nephrosclerosis?
Chronic inflammation
Increased interstitial CT (fibrosis, scarring)
Atrophic glomeruli and tubules
Hyaline arteriosclerosis
What macroscopic changes occur in renal artery stenosis?
Atrophy (usually asymmetric)
What causes lacunar infarcts?
Hyaline arteriosclerosis
What retinal changes are caused by hypertension?
AV nipping Exudates Ischaemia Haemorrhages N.B. Due to effect of hyaline arteriosclerosis
What kind of haemorrhage does a berry aneurysm cause?
Subarachnoid
What are the histological effects of malignant hypertension?
Hyperplastic arteriolosclerosis
Fibrinoid necrosis and thrombosis
What are the pathological effects of malignant hypertension?
Retinopathy
Deteriorating renal function
Haemolytic anaemia
Encephalopathy (failure of autoregulation of cerebral blood flow)
