Week 9 - Heart Failure Drugs Flashcards
What is HF
Clinical syndrome resulting from any functional/structure impairment to the heart
Heart is unable to pump blood os sufficient amounts from the ventricles to need the bodies needs
HF facts
One of the most common hospitalization causes in Canada
5k annual deaths
5 year survival rate is 50%
Prevention is key
Heart failure (left vs right sided symptoms)
Left sided
- pulmonary edema
- coughing
- SOB
- dyspnea
Right
- venous congestion
- pedal edema
- jugular distension
- hepatic congestion
Left sided HF (how to remember)
L for lungs
R for rest of body
HF causes (4)
Inadequate contractility
Inadequate filling
Pressure overload
Volume overload
4 classes of HF (New York association classification)
1 - no physical activity limits
2 - ordinary physical work results in fatigue/dyspnea
3 - marks limitation in physical activity
4 - symptoms at rest or with no physical activity at all
Drug therapy for HF (3 types and what they do)
Positive inotropic drugs
- increase force of contraction
Positive chronotropic drugs
- increase HR
Positive dromotropic drugs
- accelerate conduction
Other types of drugs used for HF
ACE inhibitors
Angiotensin receptor blockers
B blockers
Diuretics
Drugs of choice for early treatment of HF (class + example)
ACE inhibitors
- captopril
Angiotensin 2 receptor blockers
- valsartan
Beta blockers
- bisoprolol
Loop diuretics
- furosemide
Aldosterone inhibitors
- eplerenone
After all these, digoxin is considered
ACE inhibitors mechanism of action
Prevent sodium and water resorption by inhibiting aldosterone secretion
Results in diuresis, decreasing preload of the heart
Anything that ends in pril
Angiotensin 2 receptor blockers mechanism of action
Potent vasodilators
- decrease after load on heart
Used alone or in combo with diuretics
Ex . Valsartan
Beta blockers mechanism of action
Prevent catecholamine mediated actions on the heart
Anything that ends in olol
Aldosterone antagonists mechanism of action
Prevent Activate RAA system
- cause decreased levels of aldosterone, causes sodium/water to leave, help with HF
Ex. Eplerenone
Random drugs to treat HF (2)
Hydralazine
- used in black patients
Dobutamine hydrochloride
Cardiac glycosides
Prototype: digoxin
Not used much anymore, but used usually in AFIB and to control ventricular response in HF
Cardiac glycosides mechanism of action
Increase myocardial contractility
Cardiac glycosides drug effects (3)
Positive inotropic effect
- increase force of contraction
Negative chronotropic effect
- reduce HR
Negative dromotropic effect
- decreased SA and AV node conduction
More:
- up stroke volume
- increase coronary circulation
- decreased venous pressure
- promotion of tissue perfusion
- improved symptom control
Digoxin adverse effects
Narrow therapeutic window
- 0.8-2ng/ml
- increased toxicity if low K
- dysrhythmias
- headaches fatigue etc
- colour vision
Digoxin toxicity
If hyperkalemia
- overdose or life threatening dysrhythmias
Conditions that predispose to digoxin toxicity
Hypokalemia
Pacemaker use
AV block
Hypercalcemia
Dysrhythmias
Old
VFIB
Nursing implications (general HF drugs)
- assess history
- vitals
- serum labs
- before giving, count apical pulse
- dont give if symptoms present
- avoid digoxin + fibre
- monitor for therapeutic effects and adverse
