Heart Failure

Question 1

Name 2 drugs that improve symptoms in Hf

Answer 1

• diuretics (mainstay)

* digoxin ( improve contractility )

Question 2

Name 4 drugs that improve survival in Hf

Answer 2

• Ace-i ( or arb, ARNI second and third line) and
. Beta blockers: carvedilol, bisoprolol, metoprolol
• mineralocorticoid receptor antagonists eg spironolactone, eplerenone
• oral nitrates and hydralazine (if above 3 not effective)

Question 3

Name example ARNI

Answer 3

Angiotensin receptor neprilysin inhibitor

Sacubitril/valsartan

Question 4

When are heart failure patients prescribed MRA in addition to ace-i and B blocker?

Answer 4

• HFrEF and symptomatic despite above treatment

Question 5

Name 2 MRA that may be used for chronic heart failure

Answer 5

• Spironolactone
• amiloride
• eplerenone
(K sparing diuretics)

Question 6

When are oral nitrates prescribed to chronic heart failure patients?

Answer 6

• Angina and impaired Lv systolic function

* severe renal impairment, where ace-i contraindicated

Question 7

Which vasodilators may exacerbate heart failure?

Answer 7

CCB, especially non-dihydropyridines: diltiazem, verapamil

Due to negative inotropic and chronotropic properties

Question 8

Which 2 CCB are safer in congestive heart failure?

Answer 8

Dihydropyridines (newer): amlodipine, felodopine

Question 9

Where on the nephron do loop diuretics work?

Answer 9

Ascending loop of Henle

Question 10

Where on the nephron do carbonic anhydrase inhibitors work?

Answer 10

Proximal convoluted tubule

Question 11

Where on the nephron do potassium sparing diuretics work?

Answer 11

Late distal tubule to collecting duct.

Question 12

Name 2 examples loop diuretics

Answer 12

Furosemide

Bumetanide

Question 13

Moa loop diuretics?

Answer 13

• Inhibit na/k/2cI cotransporter in luminal membrane of ascending loop of Henle
• this increase amount of sodium reaching collecting duct, therefore increase k and H secretion.
. So more sodium and water excreted: decrease cardiac preload, reduce oedema

• also inhibit calcium and magnesium reabsorption due to decrease in potential difference across cell normally generated from recycling of potassium
• indirect vasodilation.

Question 14

Name adverse effects loop diuretics (5)

Answer 14

• Renal and electrolyte abnormalities
• hypokalaemia:precipitate arrhythmic.
. Acute gout: hyperuricaemia
• hypo all electrolytes: hypok, hypoNa, hypoca, hypomg (cause cardiacexcitability)
• ototoxicity (endolymph inner ear require na/k/2Cl cotransporter

Question 15

Drug interaction with K sparing diuretics?

Answer 15

Ace-i: risk hyperkalaemia

Question 16

Name 4 indications digoxin

Answer 16

• AFib with co-existing heart failure (improve control ventricular rate and filling)
• chronic heart failure secondary to lv systolic impairment who remain symptomatic despite diuretics and ace-i. ( act as inotrope)
• severe lv systolic dysfunction with cardiac dilatation
• recurrent admissions for heart failure

Question 17

Moa digoxin?

Answer 17

Cardiac glycoside
• inhibit membrane na/k ATPase pump
• this increase intracellular na, reducing sodium gradient across membrane
• thus decreasing amount calcium pumped out by na/ca exchanger during diastole.
• intracellular calcium rise causing increased force contraction and maintain normal bp (positive in tropic effect )!

also alter electrical activity
• indirectly decrease heart rate, slow av conduction, shorten atrial action potential by stimulate vagal activity. Negative inotropic effect. Useful in af because when ventricular rate excessively high, time available for diastolic filling is inadequate so slowing hr increase sv and cardiac efficiency.
• toxic doses: indirectly increase sympathetic activity heart and cause arrhythmic including heart block.
• direct effects caused by loss intracellular potassium, high doses. Resting potential reduced causing enhanced automaticity slowed cardiac conduction and increased avn refractory period.

Direct effect alpha adrenoreceptors
• vasoconstriction
• increase peripheral vascular resistance

Question 18

Name 3 adverse effects digoxin

Answer 18

• Nausea vomiting
• visual disturbances
• fatal cardiac arrhythmia!: av junction arrhythmia, a tach, av block, v tach. Caused by indirect increase in sympathetic activity of heart and increased systolic calcium concentrations.

Toxicity exacerbated by hypo K

Question 19

Name 2 pharmacokinetic drug interactions with digoxin

Answer 19

• Reduced absorption: antacids, tetracycline, cholestyramine.
• reduced renal elimination: spironolactone, quinidine, verapamil, amiodarone

Question 20

Name 3 pharmacodynamic drug interactions with digoxin

Answer 20

• Drugs causing hypo K predispose to toxicity: diuretics, beta agonist, glucocorticoids
• drugs causing hypo mg: diuretics, alcohol
• B blockers: start slow

Question 21

Which antiarrhythhmics should be avoided in chronic heart failure (3)

Answer 21

Class 1.
• a: quinidine, procainamide, disopyramide
• b : lidocaine, mexiletine
• c : flecanide

Question 22

Which drugs may cause harm in chronic heart failure patients? (4)

Answer 22

• Thiazolidinediones (glitazones)
• NSAIDs or cox 2 inhibitors
• ditiazem or verapamil
• addition arb to combination of ace-i and MRA (cause renal dysfunction and hyperk)

Question 23

Furosemide cv indication?

Answer 23

Iv acute heart failure

Question 24

Name 3 anti cardiac remodelling drugs

Answer 24

• Mineralocorticoids
• ace-i
• beta blocker

Question 25

Name 2 adverse effects spironolactone

Answer 25

• Gynaecomastia! Menstrual disorders, male sexual dysfunction
• hyperK, hypo Na