Systemic Hypertension Flashcards
Hypertension classification
- Primary
- 90%
- aetiology unknown but has risk factors
- risk factors are multifactorial involving genetics, smoking, stress, environment, diet
- Secondary
- 10%
- high BP is secondary to an abnormality or drug
Symptoms of Hypertension
it has none, it is a silent killer
Hypertension is a risk factor for…
stroke, HF, CAD
Drugs commonly used to treat Hypertension and/or HF
ACEi/ARBS
B-Blockers
Ca+ channel blocker( not for HF)
Diuretics
T/F
ACE2 is also targetted by ACEi
False
Define
ACE2
converts AngII to Ang(1-7) whose effects are opposite to AngII(vasodilating and natriuretic)
Ang(1-7) may exert cardioprotective effect via the receptor…
Mas receptor
ACE2 in CVD prevalence in 2020
COVID19 internalises ACE2—> promotes AT1 mediated pathology–> increased CVD incidence after COVID19 infection
B-blocker mode of action
Decreases sympathetic drive to the heart —> results in lower CO, lower HR and lower TPR. Inhibits renin release as well–> decreased ang II as Kidneys symp innervated
Beta blockers are used to treat
- Hypertension but not first line
- angina
- post-MI
- Arrhythmias
- clinically stable heart failure
B1 selective antagonists are
atenolol and metoprolol
Nonselective b1 and b2 antagonists are
propanolol
B-adrenoreceptors antagonists in HF
carvedilol and nebivolol found to reduce chronic stable heart failure and decrease mortality
potentially are antiarrhythmic, anti-ischemia and reduce NA toxicity as people with chronic HF tend to have higher NA and Adrenaline
Nonhydropyridine
more specific to the heart, decreased BP, decreased HR, decreased TPR
e.g verapamil and diltiazem

dihydropyridine
less cardiac specific, lower bP by alot, increase HR as a baroreceptor reflect and decrease TPR by a lot
nifedipine and alodipine

What does Ca+ channel blockers do
cause vasodilation, reduce cardiac contractility and reduce atrioventricular conduction
order of most heart selective Ca+ channel blockers
verapamil>diltiazem>nifedipine
Ca+ channel blockers are used to treat…
hypertension, angina, supraventricular tachyarrhythmias
Verapamil is very good at
- reducing cardiac contractility
- reducing atrioventricular conduction
- good for supraventricular tachyarrhythmias
Should not use Ca+ channel blockers for…
- Heart failure
- verapamil or diltiazem when combined with B blocker
adverse effects of Ca+ blockers
- cardiac depression and bradycardia
- flushing, edema, dizziness, headache
- constipation, nausea
Define
Diuretics
Inhibit Na+ reabsorption
Mechanism of action of diuertics
increases Na+ excretion–> increases H2O excretion–> decreased BV, Venous pressure and Venous return
long term vs short term effects of diuretics
short term: initially a lowering of CO
Long term: slightly lower CO than normal, reduced TPR
3 major classes of diuretics
- Loop diuretics
- Thiazide diuretic
- Aldosterone receptor antagonists
Loop diuertics
- act on the thick ascending limb of the loop of henley to block Na+/K+2cl- symporter
- blocks 15-25% of filtered sodium reabsorption
- greatest diuretic efficacy
Thiazide diuretic
- acts on distal convoluted tubules to block na+/Cl- symporter
- 5-10% of sodium excretion
e.g hydrochlorothiazide
When treating mild to moderate hypertension with diuretics we would use…
thiazides
When treating edema due to congestive heart failure, pulmonary congestion or renal/liver disease with diuretics we would use…
Furosemide
Adverse effects of loop diuretics and thiazides
- Electrolyte imbalance
- hypokalemia
- can lead to arrhythymia
- hypokalemia
- hyperuricemia(gout)
- hypercholesterolemia
- hyperglycemia
Aldosterone receptor antagonist
- also called K+ sparing diuretics in distal tubules or collecting ducts
- inhibits mineralocorticoid receptor ( ald receptor in kidney)
- in heart inhibits ald induced fibrosis and thus improves HF
e.g spironolactone
Spironolactone clinical uses
- used in combo with thiazides and loop diuretics to produce a weak diuresis eihtout hypokalemia
- used in conditions associated with hyperlaldosteronism
- improves survival thus resurgence of interest in chf
- resitant hypertenison add on therapy maybe
Adverse effects of spironolactone
hyperkalemia
new targets fro hypertnesion
inflammation, fibrosis, RAS, AT2