Cardio - hypertension Flashcards
What is the formula for BP? BP = ?
BP = CO x PVR (cardiac output x resistance)
What is the mechanism and clinical uses(3) of thiazide diuretics?
(Hydrochlorothiazide, Chlorthalidone)
Block Na/Cl transporter
in distal convoluted tubule
Mild to moderate hypertension
combination therapy
GFR >30ml/min
What is the mechanism and clinical uses(4) of loop diuretics? (Furosemide)
Block Na/K/2Cl transporter
in thick ascending limb
severe hypertension
GFR < 30ml/min
heart failure (fluid excess)
hypercalcemia
What is the mechanism and clinical use of potassium sparing diuretics? (Epleronone, Spironolactone)
Aldosterone receptor antagonists
used in HF (RAS antagonism)
What is the mechanism and use of Methyldopa?
Stimulates centrall α2 receptors
-> less sympathethic activity -> less PVR,HR and CO
Use: hypertension in pregnancy
What is the mechanism of:
clonidine
guanabenz
guanfacin
Stimulation of central α 2 adrenoceptors
-> less sympathethic activity -> less PVR,HR and CO
What is the mechanism of: guanethidine guanadrel bethanidine debrisoquin
replaces NA in transmitter vesicles
inhibits NA release from postganglionic sympathetic neurons
What is the mechanism of Reserpine?
Blocks VMAT in adrenergic neurons
(blocking uptake of biogenic amines)
-> less CO and PVR
What is the effect of blocking ß1± ß receptors?
Less HR,CO and maybe less PVR
Less RAS activity (inhibits renin relase)
What does the following drugs have in common? atenolol acebutolo esmolol betaxolol bisoprolol metoprolol Nebivolol
They are all cardioselective ß1»_space; ß2 blockers
Which ß - blocker also induces nitric oxide synthase?
Nebivolol (ß1 + NO)
Which ß-blockers also blocks α receptors?
Labetalol and Carvedilol
ß1+ß2+α
What is the mechanism and uses(2) of:
phentolamine
phenoxybenzamine
α-blockers: nonselective
Use:
pheochromocytoma
Clonidine withdrawal
What is the mechanism and uses(2) of:
doxazosin
prazosin
terazosin
Selecive α1 -blockers
Use:
hypertension
prostatic hyperplasia
What is the mechanism and uses(2) of Hydralazine?
Release of NO by endothelial cells
Use:
hypertension
chronic heart failure
with isosorbide dinitrate
What is the mechanism and uses(2) of Minoxidil?
Opens K+ channels leading to
arteriolar vasodilation
Use:
hypertension
stimulates hair growth
What is the mechanism and uses(2) of Diazoxide?
K+ channel opening
-> arteriolar vasodilation
Use:
hypertension
insulinoma (inhibits insulin release
by opening K+ channels)
What is the mechanism and use of sodium nitroprusside (i.v.)?
Release of NO from the molecule
-> POWERFUL arteriolar and venous dilation
Use:
hypertensive emergencies
(1-10m duration of action)
What is the mechanism and use of Fenoldopam?
D1 agonist, stimulates natriuresis,
causing arteriolar vasodilation
Use:
Hypertensive emergencies
What is the mechanism of: Captopril Benazepril Enalapril Lisinopril
Blocks ACE and thus:
Angiotensin I -> angiotensin II
Bradykinin -> inactive metabolite
-> cough, less PVR
What are the uses(6) of ACE inhibitors?
Hypertension MI chronic heart failure stroke prevention Chronic kidney disease(CKD) diabetes+cardiovasc risk factors
What are toxicities(6) of ACE inhibitors?
Cough angioedema hypotension hyperkalemia TERATOGENICITY renal failure (avoid NSAIDs, aminoglycosides, and vancomycin)
Which two ACE inhibitors are not eliminated via kidneys?
Fosinopril
Moexipril
What is the mechanism and uses of:
Losartan
Candesartan
Irbesartan
Blocks Angiotensin receptor 1
Use: hypertension
What are the toxicities of sartans? (AT1 blockers)
Like ACE inhibitors
but no coughing
What is the mechanism and use of Aliskiren
Renin inhibitor
Use: hypertension
What is the mechanism and uses(2) of
Verapamil and Dilitazem?
Non dihydropyridines:
Cardioselective Ca-channel blockers
Use:
hypertension
arrythmias
What is the mechanism and uses(2) of Nifedipine and other dihydropyridines?
L-type Ca-channel blocker
-> vasodilation
Use:
Hypertension
angina
What is the downside of to rapid normalization of high BP? And when is it indicated?(3)
cerebral hypoperfusion(stroke symptoms)
Indicated if: pulmonary edema aortic dissection hemorrrhagic stroke NOT in ischemic stroke
What is the mechanism and use of:
ambrisentan
bosentan
macitentan
Endothelin receptor antagonists
Use: non-vasoreactive
pulmonary hypertension
What is the mechanism and use of:
Sildenafil
Tadalafil
Vardenafil
PDE 5 inhibitors
Use: non-vasoreactive
pulmonary hypertension
What is the mechanism and use of: beraprost epoprostenol inhaled iloprost treprostinil selexipag
prostacyclin analogues and
prostacyclin receptors agonists
Use: non-vasoreactive
pulmonary hypertension
What agents are used in the treatment of pulmonary hypertension with vasoreactivity? (test with NO)
- calcium channel blockers:
nifedipine, amlodipine, diltiazem
What is the contraindication for using diuretics in the treatment of hypertension?
Gout
What is the contraindications(2) for using B-blockers in the treatment of hypertension?
Asthma AV block (2 or 3)
What is the contraindications(3) for using non DHP CCB in the treatment of hypertension?
AV block (2 or 3) severe LV dysfunction heart failure
What is the contraindications(4) for using ACE inhibitors or sartans in the treatment of hypertension?
Pregnancy
hyperkalemia
bilateral renal stenosis
angioneurotic edema (ACE inhib)
What is the contraindications(2) for using mineralocorticoid receptor antagonists in the treatment of hypertension?
eGFR < 30mL/min
hyperkalemia
Which drugs(5) are the first line treatment for hypertension?
Thiazides Sartans ACE inhibitors Calcium channel blockers ß-blockers
Start from any of them,
but beware of comorbidities!
Which to pairs of antihypertensive drugs should never be combined?
Sartans + ACE ihibitors
ß-blockers + Verapamil
Why is ACE inhibitors preferred over Sartans? When is Sartans preferred?
They are much more effective.
Sartans is preferred if coughing
is a problem
