Heart Failure Flashcards
Name 2 drugs that improve symptoms in Hf
- diuretics (mainstay)
* digoxin ( improve contractility )
Name 4 drugs that improve survival in Hf
• 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)
Name example ARNI
Angiotensin receptor neprilysin inhibitor
Sacubitril/valsartan
When are heart failure patients prescribed MRA in addition to ace-i and B blocker?
• HFrEF and symptomatic despite above treatment
Name 2 MRA that may be used for chronic heart failure
• Spironolactone
• amiloride
• eplerenone
(K sparing diuretics)
When are oral nitrates prescribed to chronic heart failure patients?
- Angina and impaired Lv systolic function
* severe renal impairment, where ace-i contraindicated
Which vasodilators may exacerbate heart failure?
CCB, especially non-dihydropyridines: diltiazem, verapamil
Due to negative inotropic and chronotropic properties
Which 2 CCB are safer in congestive heart failure?
Dihydropyridines (newer): amlodipine, felodopine
Where on the nephron do loop diuretics work?
Ascending loop of Henle
Where on the nephron do carbonic anhydrase inhibitors work?
Proximal convoluted tubule
Where on the nephron do potassium sparing diuretics work?
Late distal tubule to collecting duct.
Name 2 examples loop diuretics
Furosemide
Bumetanide
Moa loop diuretics?
• 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.
Name adverse effects loop diuretics (5)
• 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
Drug interaction with K sparing diuretics?
Ace-i: risk hyperkalaemia
Name 4 indications digoxin
- 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
Moa digoxin?
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
Name 3 adverse effects digoxin
- 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
Name 2 pharmacokinetic drug interactions with digoxin
- Reduced absorption: antacids, tetracycline, cholestyramine.
- reduced renal elimination: spironolactone, quinidine, verapamil, amiodarone
Name 3 pharmacodynamic drug interactions with digoxin
- Drugs causing hypo K predispose to toxicity: diuretics, beta agonist, glucocorticoids
- drugs causing hypo mg: diuretics, alcohol
- B blockers: start slow
Which antiarrhythhmics should be avoided in chronic heart failure (3)
Class 1.
• a: quinidine, procainamide, disopyramide
• b : lidocaine, mexiletine
• c : flecanide
Which drugs may cause harm in chronic heart failure patients? (4)
- Thiazolidinediones (glitazones)
- NSAIDs or cox 2 inhibitors
- ditiazem or verapamil
- addition arb to combination of ace-i and MRA (cause renal dysfunction and hyperk)
Furosemide cv indication?
Iv acute heart failure
Name 3 anti cardiac remodelling drugs
- Mineralocorticoids
- ace-i
- beta blocker
Name 2 adverse effects spironolactone
- Gynaecomastia! Menstrual disorders, male sexual dysfunction
- hyperK, hypo Na
