Pathophysiology of Hypertension Flashcards
What is the difference between primary hypertension and secondary hypertension?
Primary - idiopathic (unknown origin)
Secondary - associated with other diseases or of a known aetiology
Mentioning vascular resistance in your explanation, why does altitude cause pulmonary hypertension?
Lack of O2, detected by lungs, reflex vasoconstriction, increased vascular resistance, increased pulmonary pressure
Above what pressure is Stage 1 systolic hypertension clinically diagnosed?
140/90
Above what pressure is Stage 2 hypertension clinically diagnosed?
160/100
Below what pressure is a patient considered clinically hypotensive?
90/60
List some possible underlying causes of hypertension.
Increase in total peripheral resistance
Increased sympathetic nerve activity
Balance between contraction/relaxation changes
What will an increase in extracellular Na+ cause?
Influx of Na+ into cells and subsequent depolarisation
List 6 causes of secondary hypertension.
Renal disease Diabetes Endocrine disorders Coarctation (narrowing) of the aorta Some drugs Pregnancy (leading to eclampsia (spasms))
Name some modifiable risk factors of hypertension.
Exercise Diet Obesity Smoking Alcohol intake Stress
What are some non-modifiable risk factors of hypertension?
Age Family history Abnormal inhibition of Na+/K+/ATPase pump Male African/Caribbean origin Personality type
What are the major causes of death associated with hypertension? Use percentages on each to represent proportions.
Heart failure 50%
Myocardial Infarction 20%
Stroke 20%
Renal failure 10%
What 3 affects can hypertension have on vasculature?
Accelerated atherosclerosis
Stroke
Retinopathy
How can hypertension cause heart failure?
Pressure overload from increased total peripheral resistance leading to left ventricular hypertrophy
OR
Volume overload due to renal failure, decreased actin-myosin overlap
What happens in renal failure?
Autoregulation tries to protect the glomerulus
Albumineria (albumin moving out of the blood, into the urine)
Continued high pressure thickens and narrows arteries
Urine formation falls due to decreased clearance of creatinine, urea and waste products and volume overload
What are some of the causes of pulmonary hypertension?
Hypoxia Genetics Endothelial dysfunction Reynaud's disease Blockage of or damage to pulmonary vessels Drug side effects
In what percentage of cases is hypertension idiopathic and therefore primary?
90%
With subsequent ambulatory or home blood pressure monitoring (ABPM or HBPM), above what pressure is considered Stage 1 hypertension?
135/85mmHg
With subsequent ambulatory or home blood pressure monitoring (ABPM or HBPM), above what pressure is considered Stage 2 hypertension?
150/95mmHg
What is classed as severe hypertension?
180mmHg systolic OR 110mmHg diastolic
What are some potential causes of primary hypertension?
Endothelial damage –> decreased NO production
Increased wall thickness to lumen size ratio
Increased extracellular Na+ (vascular reactivity)
Pathological Na+/K+ -ATPase pump inhibition
What are the two main factors that can be added together to increase BP?
Increased vascular reactivity
Increased sympathetic nerve activity
What is retinopathy the result of?
Hypertension causes damage to the retinal arteries. Narrowing occurs and following occlusion, oedema and haemorrhage arise
What can retinopathy lead to if left untreated?
Blindness
In a case of stage 3 severe hypertension, what abnormality would you expect to see on an ECG?
Inverted T waves
How long can a typical 35 year old male expect to live with normal BP?
38-40 years more
How long can a typical 35 year old male expect to live with Stage 1 hypertension?
15-20 years more
How long can a typical 35 year old male expect to live with Stage 3 severe hypertension?
8-10 years
A 2mmHg rise in systolic BP accounts for what percentage rise in risk of:
Heart disease?
Stroke?
Heart disease: 7%
Stroke: 10%
What is the recommended treatment course for a hypertensive patient who is aged under 55 years old?
A - ACE inhibitor or ARB
C - Calcium channel blocker
D - Diuretic
B - Beta blocker, Alpha blocker or Spironolactone
What is the recommended treatment course for a hypertensive patient who is either aged over 55 years old or is of African or Caribbean origin, of any age?
C - Calcium channel blocker
A - ACE inhibitor or ARB
D - Diuretic
B - Beta blocker, Alpha blocker or Spironolactone