Drugs Used In Heart Failure Flashcards
Risk factors for HF:
- HTN
- coronary artery disease
- MI
- diabetes
- family history of cardiomyopathy
- use of cardiotoxins
- obesity
HF with preserved ejection fraction is ______ heart failure
Diastolic
What can you do to reduce systolic HF?
↓ afterload and ↓ preload
What is the effect of the ↑ angiotensin II in the compensatory physiological response to HF?
- ↑ preload
- ↑ afterload
- remodeling
What is the definition of preload?
The force stretching the ventricles; ↑ length of stretching of myocardial cells → ↑ force of contraction
Why would ↓’ing preload in CHF patients ↑ the contractility
In CHF patients there is so much volume overload that the preload is too high and that results in poor contractility
What is afterload?
The force against which ventricles must act: vascular resistance (aortic BP)
How is calcium removed from cardiac muscle cells?
- Na/Ca exchange
- storage in sarcoplasmic reticulum
What should patients with chronic heart failure NOT take?
- NSAIDS
- alcohol
- calcium channel blockers
What drugs are used to treat HFrEF (systolic HF)
HFrEF = heart failure with reduced ejection fraction
- diuretics
- spironolactone
- ACEI’s and ARB’s
- direct vasodilators (hydralazine and nitrates)
- β blockers
- ionotropic agents
What drugs are used to treat HFpEF (diastolic HF)
- diuretics (careful not to ↓ preload too much because that can ↓ filling)
- ACEI/ARB’s
- β blockers
- calcium channel blockers
Calcium channel blockers is a class of drugs uses to treat only _________ type of HF
Diastolic HF; helps with relaxation of ventricles to aid in filling
Can you give β blockers to treat systolic HF?
Yes; β blockers is prescribed for BOTH types of HF
What are the 4 different AHA stage classifications of HF?
Stage A: high risk fo developing HF
Stage B: asymptomatic HF
Stage C: symptomatic HF
Stage D: refractory end stage HF
Describe the 4 classes of the NYHA HF symptom classification
Class I: no symptom limitation with ordinary physical activity
Class II: ordinary activity somewhat limited by dyspnea (long distance walking, climbing 2 sets of stairs)
Class III: exercise limited by dyspnea with moderate workload (short distance walking, one flight of stairs)
Class IV: dyspnea at rest with very little exertion
What is the 1st line treatment for people with stage C CHF?
Diuretics, ACEI, and β blockers
In addition to β blockers and diuretics, what else would you give in symptomatic patients with CHF? ACEI or ARB?
ACEI
What is the effect of diuretics on preload and afterload?
↓ preload: ↓ plasma volume and thus ↓ venous return to the heart and thus ↓ cardiac workload and oxygen demand
↓ afterload: ↓ plasma volume causes a ↓ in BP
What are some of the effects of ACEI in patients with CHF?
↓ preload: ↓ Na and water retention
↓ afterload: ↓ vascular resistance and BP
Both above will ↑ CO
Can also undo some of the remodeling of the heart
What drugs are ACEI’s?
- captopril
- lisinopril
- enalapril
What patients are recommended to take ACEI’s?
- symptomatic HF
- asymptomatic HF patients with ↓ LVEF or history of MI
- patients at high risk for developing HF due to : atherosclerotic disease, obesity, DM or HTN
Patient who is asymptomatic but has a history of MI, what kind of drug would you recommend?
ACEI
Contraindications of ACEI?
- pregnant women
- patients with bilateral renal artery stenosis
- previous history of angioedema
CANT GIVE ARB’S TO pregnant patients or those with bilateral renal artery stenosis
Candesartan and valsartan are what kind of drugs?
ARB’s
When would you give someone an ARB?
When you cant give an ACEI such as for patients who have severe cough or angioedema
What drugs are ARB’s?
Candesartan and valsartan
Direct vasodilators are given in combination of:
- Hydralazine (arterial dilation which ↓ afterload)
- isosorbid dinitrate (venous dilation will ↓ preload)
Produces same effect of ↓ preload AND afterload like with ACEI
When would prescribe concurrent use of hydralazine and isosorbide dinitrate?
- patients who cant tolerate ACEI or ARB’s
- African American patients with advanced HF as an adjunct to standard therapy
What medication therapy would you give to a pregnant patient with CHF?
- hydralazine + isosorbide dinitrate because ACEI’s and ARB’s are teratogenic
An African American patient is currently taking ACEI, β blocker and a loop diuretic to treat his CHF but he still has symptoms. What would be the next step in therapy?
Direct vasodilators: concurrent use of hydralazine and isosorbide dinitrate
Lupus like syndrome is an adverse effect seen with __________
Hydralazine
Contraindications with direct vasodilators
Can’t give sildenafil
AE of hydralazine:
- tachycardia
- peripheral neuritis
- lupus like syndrome