Hypertension Flashcards
How many people per year die of hypertension in the USA?
1,000,000
When does blood pressure vary naturally?
Time of day
Age
Sex (women have lower BP due to hormones)
What are the diastolic hypertension criteria?
>85 = normal 85-89 = high normal 90-104 = mild hypertension 105-114 = moderate hypertension >114 = severe hypertension
What are the systolic hypertension criteria?
Less than 140 = normal
140-159 = Borderline systolic hypertension
>160 = isolated systolic hypertension
What is secondary hypertension?
Consequence of a clinical condition/ due to another pathology
What is the equation for mean arterial blood pressure?
MABP = CO x TPR (total periperal resistance)
What tends to happen to CO and tpr with age?
CO decreases
TPR increases
What are the likely causes of essential hypertension?
Cardiac dysfunction
Vessel abnormalities
Kidney dysfunction
How can cardiac dysfunction cause hypertension?
It is due to a response in stress = catecholamines
Too much CO
How do vessel abnormalities cause hypertension?
Sympathetic NS = greater innervation = abnormal = more innervation of blood vessel
Local factors eg Low endothelium derived relaxing factor and smooth muscle ion channel defects
Also muscle hypertrophy/rigidity - vascular remodelling when smooth muscle increases = increased BP
What are the known enviromental risk factors for hypertension?
Diet and obesity
Adoption of the Western lifestyle
Salt intake
Vitamin D deficiency
Which genes show the most evidence that they are linked to hypertension?
Polymorphisms in Angiotensinogen and ENaC
What can cause secondary hypertension?
Renal disease
Renal artery stenosis
Pheochromocytomas
Hormone inbalance
How can renal disease cause hypertension?
Angiotensin system is affected
Nephron function is impaired
Blood volume increases = increase in BP
If blood pressure increases the kidney may be damaged further
Tumours where can affect blood pressure and how?
On the adrenal glands
Aldosterone levels increase
What are the symptoms of hypertension?
Can be asymptomatic but can cause flushing, sweating, blurred bision and headaches
What is arteriosclerosis?
Compliance decreases - increases hypertension
What is artherosclerosis?
A build up of plaques
What are aneurysms?
An increase in aortic diameter from 2.5cm to 8+cm
If this bursts death can occur quickly due to sudden drop in BP
Symptoms can include backache
Which artery is most likely to burst?
The middle cerebral artery
Problematic as it supplies most of the cortex = profound damage
High systolic BP = thrombosis
What are the non-pharmacological treatments for hypertension?
Weight loss Exercise Diet - reduce salt, alcohol and caffiene Quit smoking Relaxation
What are the pharmacological treatments for hypertension?
Diuretics Sympatholytics B blockers Calcium channel blockers RAA system
Give an example of a diuretic and what it does
More wee is produced as thiazides cause increased Na and Cl excretion
What are sympatholyitcs?
Alpha channel blockers
eg clonidine decreases CNS sympathetic output
eg prozasin relaxes smooth muscle and decreases TPR
What is propanalol?
A beta blocker
It decreases heart rate and contractility
What is minoxidil?
Calcium channel blocker which decreases cardiac contractility and vascular muscle
What is manidipine?
Selective calcium channel blocker which works on smooth muscle
What is moexipil?
Inhibits ACE to decrease blood pressure
Which family of drugs block AGII receptors?
The sartan family
