Hypertension Flashcards
What two systems are involved in hypertension?
Pulmonary or Systemic circulation
What is primary HTN? What causes it? Risk factors?
HTN of unknown etiology (95% of cases). Risk factors are age, race (increased for African Americans and decreased for Asians), obesity, stress, lack of physical activity and high salt diet
What is secondary HTN? What causes it?
HTN due to an identifiable etiology (5% of cases), Renal artery stenosis is a common cause (renovascular HTN). Stenosis decreases blood flow to glomerulus. JGA responds by secreting renin which converts ATI to ATII by ACE. ATII raises BP. LEads to HTN with increased plasma renin and unilateral atrophy of the affected kidney due to low blood flow. Not seen in primary HTN.
How does Angiotensin II raise blood pressure?
- Contracting arteriolar smooth muscle increasing total peripheral resistance and 2. Promoting adrenal release of aldsterone which increases resorption of Sodium in the distal convoluted tubule (expanding plasma volume).
What is a cause of stenosis in elderly males?
Artherosclerosis.
What is a cause of stenosis in young females?
Fibromuscular dysplasia which is developmental defect of the blood vessel wall resulting in irregular thickening of large and medium sized arteries, especially the renal artery.
What is malignant HTN? Where does it arise from? How does it present?
Severe elevation in blood pressure (>180/120 mm Hg); comprises
What is malignant HTN? Where does it arise from? How does it present?
Severe elevation in blood pressure (>180/120 mm Hg); comprises
What is secondary HTN? What causes it?
HTN due to an identifiable etiology (5% of cases), Renal artery stenosis is a common cause (renovascular HTN). Stenosis decreases blood flow to glomerulus. JGA responds by secreting renin which converts ATI to ATII by ACE. ATII raises BP. Leads to HTN with increased plasma renin and unilateral atrophy of the affected kidney due to low blood flow. Not seen in primary HTN.
