Week 3 - Hypertension Flashcards
Define Hypertension
Consistent elevation of systemic arterial blood pressure.
What causes Hypertension
- A sustained increase in peripheral resistance (vasoconstriction of the arterioles)
- An increase in circulating blood volume (cardiac output)
What is the diagnosis of hypertension
- When the systolic blood pressure is equal to or greater than 140 mmHg or diastolic pressure is 90 mmHg or greater
- Can be be combined systolic and diastolic hypertension
- Localised systolic hypertension
What is primary hypertension
Essential or idiopathic hypertension, no known cause
What is secondary hypertension
Caused by an underlying disease process (e.g. kidney disease, hormone imbalances, drugs)
What are the rusk factors of primary hypertension
- Family history
- Age
- Smoking
- Obesity
- Alcohol consumption
Explain why smoking is a risk factor for hypetenstion
The nicotine in cigarette smoke is a potent of vasoconstrictor that can elevate systolic and diastolic blood pressure
What is the pathophysiology mechanism of primary hypertension
- Sympathetic nervous system
- Natriuretic peptides
- Renin-angiotensin-aldosterone system
- Inflammation, endothelial dysfunction and insulin resistance:
→ Increase in peripheral resistance
What is the role of the sympathetic nervous system in hypertension
- Increased sympathetic nervous system activity causes increased heart rate and systemic vasoconstriction → Leads to increased peripheral resistance.
- Over time → Vascular remodelling occurs, narrowing the arteries.
- Result → Permanent increases in peripheral resistance.
Study the renin–angiotensin–aldosterone system
What two factors contribute to increased blood pressure?
- Vasoconstriction
- Sodium & water retention by the kidneys.
What are natriuretic peptides, and what is their function?
- Hormones
- Regulate blood pressure by promoting vasodilation
- Reduces aldosterone to decrease sodium & water retention.
What triggers the release of natriuretic peptides (ANP & BNP)?
- Increased blood pressure
- Increased blood volume stretch the heart walls, causing the release of ANP from the atria and BNP from the ventricles.
What are the effects of ANP and BNP on the cardiovascular system?
- Reduce aldosterone → Less sodium & water retention.
- Cause vasodilation → Decrease vascular resistance.
What happens when natriuretic hormones or the renin-angiotensin-aldosterone system (RAAS) become dysfunctional?
- Increases vascular tone + sodium & water retention → Elevated blood volume.
- Causes renal dysfunction → Further sodium retention.
- Leads to a vicious cycle of increasing blood pressure.
What is secondary hypertension?
High blood pressure caused by an underlying disease or medication that increases peripheral vascular resistance or cardiac output.
What are some common causes of secondary hypertension?
- Kidney disease
- Adrenocortical hormonal imbalances (e.g., primary hyperaldosteronism)
- Certain medications (e.g., oral contraceptives, corticosteroids, antihistamines)
Can secondary hypertension be reversed?
Yes, if the underlying cause is removed before permanent structural changes occur, blood pressure can return to normal.
What are the symptoms of early-stage secondary hypertension?
Usually, there are no clinical symptoms other than elevated blood pressure.
What happens if secondary hypertension is not detected and treated?
It can lead to organ and tissue damage, especially affecting the kidneys and tissues outside the vascular system.
What causes the most clinical manifestations of hypertensive disease?
End-organ damage and damage to tissues outside the vascular system (e.g., kidneys).
What are some lifestyle modifications to help manage hypertension?
- Increase exercise levels
- Make dietary modifications (reduce salt, eat a healthy diet)
- Cease smoking
- Limit alcohol intake
- Lose weight
How does increasing exercise help manage hypertension?
It improves cardiovascular health, reduces stress, and lowers blood pressure.
Why is it important to limit alcohol intake for hypertension management?
Excessive alcohol consumption can raise blood pressure and increase the risk of heart disease.
What factors determine the need for antihypertensive drug therapy?
Severity of hypertension
Extent of end-organ damage
Why is weight loss important in hypertension management?
Losing weight reduces strain on the heart and helps lower blood pressure.
