The Cardio Vascular System - Blood Pressure And CVS Disease (w8) Flashcards
What is blood pressure ?
The pressure exerted on the walls of a blood vessel (largely referred to as arterial pressure)
What units is blood pressure measured in ?
mmHg
What does blood pressure vary in ?
Age and pathological condition of a patient
What is systolic BP?
Blood pressure measured during heart contraction
What is Diastolic BP ?
Blood pressure measured during heart relaxation
What are the three key ways blood pressure is regulates ?
1) autoregulation
2) Neural
3) hormonal
Why is hypovolemia ?
An increase in tissue fluid osmolarity (loss of blood volume) triggers ADH release.
How does ADH play a part in ovulating blood pressure ?
Antidiuretic Hormone (vasopressin)
ADH is secreted by the cells in the hypothalamus, transported to the posterior pituitary and stored until nervous stimuli.
1)ADH signals kidneys to reabsorb more water
2)Prevent the loss of fluids in the urine.
3)Increase overall fluid levels
4)ADH constricts peripheral vessels.
5)Restore blood volume and pressure.
How does the atrial natriuretic hormone/ peptide modulates BP ?
Atrial Natriuretic Hormone/peptide
Secreted by cells in the atria of the heart (B-type ANH by ventricle)
Natriuretic hormones are antagonists to angiotensin II.
Prevent aldosterone release
Promotes loss of sodium and water from the kidneys.
Suppress renin, aldosterone, and ADH production and release.
Promotes loss of fluid from the body
Blood volume and blood pressure drop.
Restore blood volume
How does catecholamines (adrenaline/ noradrenaline) modulate BP ?
Catecholamines: Adrenaline/Nor-adrenaline
Released by the adrenal medulla
Enhance and extend the body’s sympathetic activity (“fight-or-flight” response)
Increases
Heart rate
Force of contraction
Vasoconstriction (non essential organs)
Energy mobilisation to liver, muscle and heart
(Fight or flight)
How does erythropoietin modulate BP ?
Erythropoietin
Blood flow and/or oxygen levels decrease (Hypoxia).
EPO is released by the kidneys
EPO stimulates the production of erythrocytes within the bone marrow. It is a vasoconstrictor.
Increase
Blood viscosity, resistance, and pressure
Decrease
Blood flow
What are the risks of high blood pressure ?
-heart disease
-heart attacks
-strokes
-heart failure
-peripheral arterial disease
-aortic aneurysms
-kidney disease
-vascular dementia
Give 5 examples of cardiac disease …
- Heart failure (more common in men, because they have more testosterone and therefore more RBC)
- Cardiomyopathy
- Myocarditis
- Endocarditis (inflammation)
Give 4 examples of vascular disease …
- Aortic aneurysm
- coronary heart disease
- cerebrovascular disease
- renal artery stenosis
