Hypertension + Heart failure Flashcards
Define blood pressure
Force per unit area acting on vessels
Cyclical
MAP = CO X TPR
CO = SV X HR
What is the role of autocoids in blood pressure regulation?
Eg bradykinin, nitric oxide; act on vascular smooth muscle + endothelium
Acute BP maintenance working along with sympathetic NS + RAAS
Describe the relationship between the radius of a vessel and the resistance to flow
4th power relationship
Resistance to flow inversely proportional to vessel radius
Vasoconstriction- increased smooth muscle tone thus smaller lumen diameter - increased TPR- increased BP
Describe the pathophysiology and effects of hypertension (particularly on vasculature)
- Vascular remodelling, hypertrophy, thickening
- Hyperinsulinaemia and hyperglycaemia leading to endothelial dysfunction + ROS formation
- Downregulation of NO signalling
- Permanent hypertrophy of vasculature leading to increased TPR + reduced compliance
Increased morbidity + mortality
Give some examples of end organ damage due to hypertension
- Renal disease
- Peripheral vascular disease
- Anueurysms
- Vascular dementia
- Retinal disease (retinopathy)
Hypertensive heart disease- left ventricular hypertrophy seceondary to increased afterload; dilated heart failure
Why is there a greater prevalence of hypertension in men?
Women have cardioportective effects pre-menopause from high oestrogen levels
Post-menopause, the risk of hypertension in women catches up to men
Despite hypertension often persenting asymptomatically, why is it necessary to treat?
To slow down/prevent progression of acute coronary syndromes, chronic heart disease, strokes
Reducing CVD risk
What is the NICE guideline for defining hypertension?
140/90 mmHg = hypertension
What are the main types of hypertension and which is most prevalent?
Primary/essential/idiopathic- most common
Secondary- phaeochromocytoma, thyroid disease
Pre-hypertensive state
Isolated systolic/diastolic hypertension
White coat/clinic hypertension
Describe the best practice for a clinical diagnosis of hypertension
Sitting, relaxed, arm supported
If there is a >15 mmHg difference between both arms, repeat measure + use arm with higher reading
ABPM/HBPM for white coat syndrome patients
CVD risk + end organ damage assessed
When may emergency treatment be required for hypertension ie what is considered a hypertensive emergency?
BP > 180/120 mmHg
+
Clinical signs eg papilloedema, retinal haemorrhage
What is the target BP for someone <80 yrs of age and for someone with T2DM? (ie at what BP should treatment be initiated?)
140/90
What is the target BP for someone >80 yrs of age? (ie at what BP should treatment be initiated?)
150/90
What is the target BP for someone with T1DM?
135/85 (lower if experiencing severe T1DM complications)
Define stage 1 hypertension
STAGE 1:
Clinic BP 140/90- 159/99
ABPM/HBPM 135/85 - 149/94
Define stage 2 hypertension
Clinic BP 160/100 - <180/120
ABPM/HBPM:
150/95 or higher
Define stage 3 (severe/resistant) hypertension
Clinic systolic <180
OR
Clinic diastolic > 120 mmHg
Define the BP ranges for pre-hypertension and give some lifestyle modifications to reduce CVD risk
>120/80 + <140/90 mmHg
Lifestyle advice
Reduced dietary sodium intake
List the main therapeutic agents used for primary hypertension
- ACE inhibitors
- Angiotensin (AT1) receptor blockers- ARBs
- Calcium channel blockers- CCBs
- Diuretics- thiazide, thiazide like
Targetting RAAS
Where is ACE found and what does it do?
Luminal surface of capillary endothelial cells, predominantly in LUNGS
Catalyses conversion of angiotensin 1 to POTENT VASOCONSTRICTOR angiotensin 2