| When does BP rise to a maximum | Rises to a maximum in systole- the systolic pressure |
| How do you calculate BP and CO | BP = CO * TPR
CO = HR * SV |
| When does BP rise to a minimum | Falls to a minimum in diastole- the diastolic pressure |
| What does stroke volume depend on ( what factors ) | Preload → venous return
Load → inherent pumping power ( contractility )
Afterload → = pressure against which the heart must pump ( pressure in the aorta ) |
| What are the 2 mechanisms for control of Blood Pressure | Fast acting for immediate pressure changes Baroreceptor reflexes act on heart (CO) and blood vessels (TPR) via autonomics ( Sympathetic and Parasympathetic )
Slow acting long term responses act on RAAS (Renin Angiotensin Aldosterone System) via kidneys to regulate blood volume |
| What is the difference between primary and secondary hypertension | Primary hypertension --> Unknown cause , most common
Secondary hypertension --> Defined cause, e.g. renal , endocrine or pregnancy |
| What are the 2 pathophysiology of hypertension in the heart | Muscle hypertrophy
- Left ventricle works harder to combat high wall pressure
- Due to muscle hypertrophy, there is higher demand of oxygen which could lead to LV ischemia and
failure→ pulmonary congestion and oedema
Atherosclerosis :
- Endothelial damage in coronary arteries by atheroma which leads to loss of elasticity and hardening
- Narrowing and reduced oxygen supply
- Angina →infarction → heart failure |
| What are the 2 mechanisms of a stroke and TIA can be caused in the brain | Atherosclerotic plaques or thrombi in carotid or cerebral vessels which can embolize and block brain vessels
Brain micro-aneurysms can rupture → hemorrhagic stroke |
| What are some causes of secondary hypertension | Renal : renal artery stenosis, glomerulonephritis
Endocrine :
Cushing syndrome adrenocortical hyperplasia
Conn syndrome primary hyperaldosteronism
Pheochromocytoma
Thyroid dysfunction
Mechanical : coarctation of the aorta
Pregnancy : pre-eclampsia and hypertension |
| What can happen due to hypertension in the kidneys | Nephrosclerosis damages vessel walls of nephron
Reduced blood supply leading to ischaemia
Which can lead to atrophy of renal glomeruli and tubules
Progressive renal failure |
| How would you diagnose hypertension | BP > 140/90 at clinic
BP > 135/85 after ABPM or HBPM
Also examine retina by fundoscopy, Femoral pulses and Renal bruit |
| What are some investigations for hypertension | ECG - for left ventricle hypertrophy
Echocardiogram
Blood --> U/E, cholesterol, glucose and steriods
Urine --> Protein, blood
Renal ultrasound |
| What is a hypertensive emergency | BP > 200/130 with evidence of organ damage
Headache, visual disturbance
Papilloedema + retinal haemorrhages
Encephalopathy, heart failure, renal failure |
| What are some management strategies for hypertension | If it is secondary then treat the cause
If primary then there are 2 ways
Non-drugs --> Lifestyle changes
Drugs --> Angiotensin blcokers ( ACEi/ARB ) , Calcium channel blockers , Diuretics and beta blockers
Annual Review |
