Hypertension

Question 1

Definition of hypertension

Answer 1

sustained BP of 140/90mmHG or above

Question 2

Causes of hypertension (2)

Answer 2

1. Primary/Essential HTN (90-95%)
   - idiopathic, multifactorial, complex
   - influenced by envt (stress, smoking, obesity, inactivity, salt)
2. Secondary HTN (5-10%)
   - Renal
   - Endocrine
   - Neurologic
   - Aortic
   - Labile

Question 3

Effects of hypertension (4)

Answer 3

1. Blood vessels - arteriolosclerosis, accelerated atherosclerosis, aortic aneurysms
2. Heart - hypertensive heart disease
3. Kidneys - nephrosclerosis
4. CNS - cerebral hemorrhage, cerebral thrombosis, hypertensive encephalopathy

Question 4

Definition of arteriolosclerosis

Answer 4

• hypertensive vascular disease

- degenerative changes (hyaline/proliferative thickening) in the walls of small arteries & arterioles

Question 5

Types of arteriolosclerosis (2)

Answer 5

1. Hyaline arteriolosclerosis

2. Hyperplastic arteriolosclerosis

Question 6

Features of hyaline arteriolosclerosis

Answer 6

• present in benign HTN
• homogenous pink hyaline thickening + luminal narrowing
• due to plasma protein leakage across injured endothelial cells & increased smooth muscle cell matrix synthesis

Question 7

Features of hyperplastic arteriolosclerosis

Answer 7

• present in malignant HTN
• ‘onion-skin’ lesions (concentric laminated thickening + luminal narrowing)
• fibrinoid necrosis

Question 8

Pathogenesis of hypertensive heart disease (L sided - systemic & R sided - cor pulmonale)

Answer 8

• HTN - LV pressure overload - LV hypertrophy (increased wall thickness & stiffness) - impairs diastolic filling - LA dilation - LV failure
• LV failure leads to pulm venous HTN, chronic heart failure, sudden death
• Acute cor pulmonale: PE - RV dilation
• Chronic cor pulmonale: pulm HTN - RV pressure overload - RV hypertrophy & dilation - RV failure

Question 9

Features of malignant hypertension

Answer 9

• in 5% of hypertensive patients
• rapidly rising BP
• systolic >200mmHg, diastolic >120mmHg
• Clinical manifestations: renal failure, retinal hemorrhage, papilledema