Hypertension

Question 1

Refers to raised blood pressure in the systemic circulation

Answer 1

HTN

Question 2

Systolic Blood Pressure (BP) >

Answer 2

140mmHg

Question 3

Diastolic Blood Pressure (BP) >

Answer 3

90mmHg

Question 4

Hypertension may be:

Answer 4

a. Essential (primary; 95% of cases): Absence of an identifiable secondary cause
b. Secondary (5% of cases): Presence of an identifiable underlying cause

Question 5

Causes of Secondary Hypertension

Answer 5

Chronic renal disease
Coarctation of the aorta
Endocrine diseases
Drugs: Steroids, oral contraceptives, NSAID
Pregnancy (pre-eclampsia)

Question 6

Main clinical complications of Hypertension:

Answer 6

• Retinopathy
• Cerebral haemorrhage (“haemorrhagic stroke”); d\t rupture of tiny CharcotBouchard aneurysms; the latter develop as a result of weakening of arteriolar
  wall
• Atherosclerosis (Cerebral infarct, Ischaemic Heart Disease)
• Subarachnoid haemorrhage; due to rupture of a Berry aneurysm; the latter as a result of combined hypertension and atherosclerosis in genetically predisposed cerebral vessels
• Aortic dilatation → Aortic dissection
• Pressure overload → Left Ventricular Hypertrophy (LVH) → Heart Failure
• Renal Failure

Question 7

Effects of Hypertension on VESSELS

Answer 7

➢ Large and medium-sized arteries-> Acceleration of atherosclerosis
➢ Small arteries (arterioles) -> Hyaline Arteriolosclerosis

Question 8

Effects of Hypertension on HEART Hypertensive Heart Disease:

Answer 8

➢ Accelerates coronary artery atherosclerosis, which worsens Ischaemic Heart Disease ➢ Causes Left Ventricular Hypertrophy
- Left ventricle must overcome the increased pressure in the systemic circulation → Compensatory Left Ventricular Hypertrophy
- Progression of LV Hypertrophy → Increase in metabolic demands of myocardium Heart with time becomes less effective, since:
1. 2. 3.
Myocardium becomes stiff, due to hypertrophy
Distance for O2/nutrients’ diffusion increases
Atherosclerosis is accelerated
Finally, the hypertrophied LV decompensates and fails (left heart failure)
Clinical manifestations of Hypertensive Heart Disease:
- Myocardial ischaemia/infarction
- Arrhythmias (e.g. atrial fibrillation)
- Progressive Left Heart Failure