Treatment of HTN and Arrhythmia

Question 1

What are the different types of diuretics for HTN?

Answer 1

Thiazide: Inhibit sodium
reabsorption
(distal convoluted
tubule) (chlorothiazide, Hydrochlrothiazide)
Loop diuretics: Inhibit reabsorption of sodium & chloride (Loop of
Henle) (Furosemide, Torsemide)
K+ Sparing: Prevent secretion of K+ (Spironolactone, Triamterene)

Question 2

what are common side effects and adverse reactions of using diuretics?

Answer 2

*fluid loss: orthostatic hypo, changes in mental
*electrolyte imbalance: cardiac arrythmias, GI disturbance, fatigue, hypokalemia
*K+ sparing: hyperkalemia

Question 3

What are the effects of angiotensin II?

Answer 3

Vasoconstriction, stimulate aldosterone, stimulate ADH, induce thirst, increase fluid intake, chronic activation of RAS (persistent increase in BP)

Question 4

what is the MOA of ACE inhibitors?

Answer 4

*Inhibition of Ang II formation which decreases vasoconstriction which lowers BP
*inhibition of aldosterone secretion which decreases sodium and water retention which lowers BP

Question 5

What are common ACE inhibitors and their side effects?

Answer 5

-pril
*Benazepril, Captopril, Cilazapril, Enalapril, Fosinopril, Lisinopril
*side effects: dry cough, hyperalkemia, acute kidney damage, angioedema, fetotoxicity

Question 6

What is the MOA of angiotensin receptor blockers (ARBs)?

Answer 6

Blocks Ang II receptors to prevent vasoconstriction and release of aldosterone from the adrenal glands

Question 7

What are common ARBs and their side effects?

Answer 7

-sartan
*Candesartan, Irbesartan, Losartan, Telmisartan, Valsartan
*Side effects: fetotoxicity, acute kidney damage, hyperkalemia

Question 8

What can be taken if a patient can not tolerate ACE inhibitors?

Answer 8

ARBS

Question 9

What is the MOA of calcium channel blockers?

Answer 9

Blockcalcium from entering the cells of the heart and arteries. Calcium causes the heart and arteries to squeeze more strongly. By blocking calcium, calcium channel blockers allow blood vessels to relax and open

Question 10

what are common CCB and their side effects?

Answer 10

*Verapamil, Diltiazem, Amlodipine, Felodipine, Nifedipine
*side effect: dizziness, flushing, headache, fatigue, peripheral edema

Question 11

What are beta-1 selective beta blockers?

Answer 11

Atenolol, Metoprolol, Acebutolol, Esmolol, Carteolol, Betaxolol
Bind to B-1 receptors on the heart to block the effects of epinephrine and norepinephrine

Question 12

What are side effects and adverse reactions of beta blockers?

Answer 12

Bronchoconstriction (wheezing and dyspnea), decrease HR and myocardial contractility, orthostatic hypotension, depression, lethargy, decreased libido

Question 13

What is the MOA of alpha blockers? What are common drugs?

Answer 13

Block the A-1 adrenergic receptor on vascular smooth muscle to cause decrease in vascular resistance; Can cause reflex tachycardia and orthostatic hypotension
Drugs: Prazosin, Terazosin, Doxazosin

Question 14

what are alpha-2 agonists? what are common drugs and their adverse effects?

Answer 14

*clonidine and methyl dopa
MOA: stimulate A-2 adrenergic receptors in the brain to reduce sympathetic outflow; will decrease HR, CO, and vascular resistance
AE: dry mouth, dizziness, sedation

Question 15

What are vasodilators? What are common drugs and their adverse effects?

Answer 15

Hydralazine and Minoxidil
MOA: activate K+ channels causing hyperpolarization of the smooth muscle membrane preventing calcium influx resulting in the arteriolar smooth muscle relaxing
Indication: Mod to severe HTN
Adverse effect: reflex tachycardia, sodium and water retention, orthostatic hypotension

Question 16

what are Renin inhibitors?

Answer 16

Aliskiren
MOA is similar to ACE inhibitors and ARBs
Must NOT be used during pregnancy

Question 17

Why do cardiac arrythmias occur?
What is considered bradycardia or tachycardia?

Answer 17

Cardiac arrythmias occur primarily because of disturbances in electrical impulse generation or conduction
Tachycardia: >100bpm
Bradycardia: <60bpm

Question 18

Name the classes of antiarrhythmic drugs

Answer 18

*Class I: Na + channel blockade
*Class II: β-adrenergic receptor blockade
*Class III: K+ channel blockade (Prolong
repolarization)
*Class IV: Ca 2+ channel blockade

Question 19

What are Class I Subclass IA antiarrhythmic drugs?

Answer 19

*Block fast Na+ channels
increase duration of action potential and prolong repolarization
*Quinidine:1st antiarrhythmic used, treats both atrial and ventricular arrhythmias, increases refractory period
*Procainamide: increases refractory period
*Disopyramide: extended duration of action, used only for treating ventricular arrythmias
*SE: torsades de pointes

Question 20

What are Class I Subclass IB antiarrhythmic drugs?

Answer 20

*shorten repolarization and decrease action potential duration
* lidocaine: block Na+ channels in ventricular cells
*Mexiletine: oral lidocaine derivate, same activity
BOTH FOR VENTRICULAR ARRHYTHMIAS
*SE: Drowsiness, seizures, hypotension

Question 21

What are Class I Subclass IC antiarrhythmic drugs?

Answer 21

*little effect of repolarization
*Flecainide: slows conduction in all parts of the heart, inhibits abnormal automaticity
*Propafenone: slows conduction and is a weak b-blocker with some Ca+ channel blockade
BEST FOR VENTRICULAR ARRYTHMIAS
*SE: visual disturbances, dizziness

Question 22

What are Class II antiarrhythmic drugs?

Answer 22

*B-adrenergic blockers
*MOA: block myocardial B-adrenergic receptors
*Propranolol: Cause b-adrenergic blockade (slows SA node and blocks arrhythmias caused by exercise); Metoprolol, Sotalol, Atenolol, Esmolol
EFFECTIVE FOR ATRIAL TACHYCARDIA AND VENTRICULAR ARRHYTHMIAS
*SE: fatigue, bradycardia, hypotension

Question 23

What are Class III antiarrhythmic drugs?

Answer 23

*Class III- K+ channel blockers cause delay in repolarization
*Amiodarone: prolong action potential by delaying K+ efflux
*Dronedarone: amiodarone analogue
*Ibutilide: slows Na+ and delays K+
*Dofetilide: prolong action potential by delaying K+ efflux
*SE: pulmonary toxicity, thyroid dysfunction, hepatotoxicity, corneal deposits

Question 24

What are Class IV antiarrhythmic drugs?

Answer 24

*Ca+ channel blockers slows the rate of AV conduction in patients with atrial fibrillation
*verapamil and diltiazem: slows SA node in tachycardia
*SE: Constipation, hypotension, bradycardia

Question 25

What is Adenosine, Digoxin, and Atropine?

Answer 25

*Adenosine: inhibits AV conduction via injection for supraventricular tachycardia
*Digoxin: reduces conduction through the AV node for atrial flutter and fibrillation
*Atropine: treats sinus bradycardia by blocking vagal effects on the SA node