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Pharmacology
Most medications improve the functional ability of the heart, making it easier to perform activities of daily living and to exercise. This is often accomplished by improving cardiac output, reducing filling pressure and neurohormone levels. The choice of medication depends on many factors, including the type of HF, the stage that it’s at and its etiology [15]. It is important to remember that an in-depth understanding of the pathophysiology underlying the illness is important before deciding on which drug therapy to pursue.
Polypharmacy - Today’s drug based heart failure treatment plans involve a plethora of medications that must be taken at various time intervals and doses. This results in a very complex set of instructions that the patient must follow. The term “polypharmacy“ was coined to describe this practice, and it has been linked with non-adherence to treatment instructions [46].
Common heart failure medications:
Diuretics | Examples: furosemide, bumetanide, ethacrynic acid
Lowers the volume of blood in the circulatory system which in turn, lowers blood pressure, making it easier for the heart to pump Most work by removing potassium (K+) Side effects: Low blood pressure, dehydration, kidney dysfunction |
Inotropes | Examples: Digoxin, Milrinone, Dobutamine Increases the force of contraction Reduces heart size Improves some arrhythmias Side effects: toxicity, nausea, irregular heart beats, stomach pain, greenish-yellow vision |
Calcium channel blockers | Vasodilator - lowers blood pressure Increased mortality and prevalence of recurrent CHF with chronic use Should only be used in patients with diastolic dysfunction Usually used in patients whose heart failure is caused by high blood pressure and who are not responding to ACE-Inhibitors [1] |
Beta-Blockers | Examples: carvedilol, metoprolol Prevents adrenaline from binding to beta I receptors in the myocardium which limits the rate of contraction, allowing time for the ventricles to fill Increases exercise capacity Appears to be cardioprotective in patients with depressed LV function [1] Side effects: slow heart rate, low blood pressure, asthma |
Angiotension-converting enzyme (ACE) - inhibitor | Examples: captopril, enalapril, lisinopril
Vasodilator Blocks the formation of angiotension II which raises blood pressure by constricting blood vessels and retaining sodium Reduces preload, afterload, right atrial pressure, and pulmonary capillary wedge pressure May reverse hemodynamic instability and symptoms [1] Side effects: persistant dry cough, low blood pressure, kidney failure |
Angiotensin II receptor blockers
| Vasodilator - lowers blood pressure Usually given to patients who cannot handle the side effects of ACE-Inhibitors |
Isosorbide Dinitrate and Hydralazine[1] | These two drugs are given in a fixed dose combination In the African American Heart Failure Trial, this drug reduced mortality in black people by 43% Does not appear to affect white people
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Medications to Avoid
Non-steroidal anti-inflammatory drugs (NSAID’s)
Ibuprofen
Naproxen
Indomethacin, piroxicam, ketoprofen, diclofenac, celecoxib, rofecoxib, moloxicam
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1. http://www.emedicinehealth.ca
15. Stromberg A, Martensson J. Gender differences in patients with heart failure. European Journal of Cardiovascular Nursing. 2003;2:7-18.
46. Vinson JM, Rich MW, Sperry JC, et al. Early readmission of elderly patients with congestive heart failure. J Am Geriatr Soc. 1990;38:1290-1295.
