C- Diuretics & RAAS Antagonists Flashcards
CO=
HR*SV
Increase Cardiac Output by increasing
Intropy
Heart Rate
Preload
Decrease CO by
Inc. Afterload
Specific Goals of Heart Failure Management with Pharmacotherapy
Reduction of congestion
Modulate neurohormonal activation
Improve flow
Used first as needed to reduce congestion
Reverse Na+ and fluid retention
Relieve volume overload: dyspnea peripheral edema
Lowers preload (LVEDP)
Diuretics
resulting in long-term stabilization, positive remodeling, and increased survival with RAAS antagonists and β-blockers
Modulate neurohormonal activation
Loop diuretics preferred because of ______- can augment with a thiazide diuretic
efficacy
may be difficult to accomplish pharmacotherapeutically with vasodilators and requires mechanical devices or transplantation
improve flow
ALDO–> Na+ sparing is the _______ but can cause K+ wasting
Major action
ALDO antagonists are ____ sparing
K+ sparing
fluid optimization with diuretics is a major part of heart failure therapy
Reduction of congestion
ALDO–> Na+ sparing is the major action but can cause ______
K+ wasting
ACE-ARB are ____ sparing
K+ sparing
Furosemide ______diructic
most common
Loop and thiazide are both ____ wasting
K+
#11: Hydrochlorothiazide #14: Furosemide (Lasix®) #42: HCTZ-Triamterene (Dyazide) #70: Spironolactone (Aldactone®)
Important diuretics
most common diuretic
Furosemide
Interactions with membrane transport proteins
• Interactions with enzymes (acetazolamide) or hormone receptors (spironolactone)
• Osmotic effects preventing water reabsorption (mannitol)
Mechanisms of diuretics
Important diructics from top 200 list
#11: Hydrochlorothiazide #14: Furosemide (Lasix®) #42: HCTZ-Triamterene (Dyazide) #70: Spironolactone (Aldactone®)
Most diuretics exert effects at __________ surface of renal tubule cells
luminal (urine)
Inhibit NaCl transport (Na+-K+-2Cl–transporter) in TAL - greatest efficacy due to large capacity of this segmen
Associated with increase in Mg++, Ca++ excretion (diminish lumen-positive potential)
Loop Diuretics
_________ diuretics act via inhibition of Na+-K+-ATPase
No, None, Nada
Diuretic agents decrease _________ at various sites in the nephron
Na+ reabsorption
In loop diuretics:
Handled by glomerular filtration and renal secretion (same organic acid transporter as uric acid)
Is the mechanism for?
Mechanism for hyperuricemia
Loop Diuretics
Use in Heart Failure
Used in HF patients with volume overload
Efficacy is enhanced with salt restriction
Furosemide most commonly used
Loop diuretics most _________ in HF
efficacious
Loop Diuretics
Adverse Reactions
Hypokalemic metabolic alkalosis
Hyperuricemia
Inhibit the Na+/Cl- cotransporter –> increased urinary excretion of NaCl
Modest diuretic effect since only 5-10% of filtered Na+ is reabsorbed here
Thiazide Diuretics
Thiazides ________ of Ca++ ( NOTE: loop diuretics decrease serum Ca++ levels)
increase reabsorption
Competitive antagonist at aldosterone receptor
Spironolactone
Vasodilation Salt / Water Excretion
ACE INHIBITORS / ANGIOTENSIN RECEPTOR BLOCKER
Adrenergic and RAAS blockers- REDUCE MORBIDITY AND IMPROVE SURVIVAL
Decreased Contractility
May worsen symptoms
BETA BLOCKERS
Adrenergic and RAAS blockers- REDUCE MORBIDITY AND IMPROVE SURVIVAL
Thiazides increase reabsorption of Ca++ ( NOTE: loop diuretics _________ Ca++ levels)
decrease serum
Salt / Water Excretion Potassium retention
ALDOSTERONE RECEPTOR BLOCKADE
Adrenergic and RAAS blockers- REDUCE MORBIDITY AND IMPROVE SURVIVAL
