Congestive heart failure drugs to avoid

Overview
Pharmacological therapy should be closely monitored and several classes of drugs should be avoided in case of HF:


 * Calcium Channel blockers: There is no direct role of these drugs in the management of HF, due to negative and possible deleterious effect in patients with HF due to systolic dysfunction . Vasoelective Calcium Channel blockers as amlodipine and felodipine have not been linked to adverse effect in HF treatment, but there is no evidence of efficacy for these drugs in the management of HF. However, amlodipine and felodipine appear to be safe for the treatment of concomitant disease in HF patients, such as angina or hypertension.


 * Antiarrhythmic agents: Negative inotropic effect exerted by most antiarrhythmic drugs can precipitate HF in patients with reduced LV function. The reduction in LV function can also reduce the elimination of these drugs leading to further drug toxicity. Other antiarrhythmic drugs can induce some proarrhythmic effect, especially class 1 agents and class 3 agents Ibutilide and sotalol (which has a negative inotropic effect); the same class 3 agents in addition to dofetilide can induce torsades to pointes.  Amiodarone is considered the safest of the antiarrhythmic drugs because of its minimal proarrhythmic effect and is generally the preferred drug for treating arrhythmias in HF patients.Dronedarone should be avoided in patients who were hospitalized with CHF (this is a boxed warning). Disopyramide is contraindicated in patients with heart failure


 * Nonsteroidal anti-inflammatory drugs (NSAID): The administration of non-selective NSAIDs in HF patients is linked with an increased risk of HF exacerbation, increased renal dysfunction, and abnormal responses to ACEIs and diuretics. COX-2 selective inhibitors have not been fully investigated, but observational studies indicate that they may be linked with an increased rate of HF exacerbation and increased mortality.


 * Aspirin benefits and risks are not well established in patients with HF and Vascular disease (includingCAD). The potential interaction between ACEIs and beta blockers is of great importance. Although no data has proven that aspirin causes more frequent HF exacerbations and interactions with those drugs, health care providers should be aware of the possibility of such risks, but no recommendation for or against aspirin therapy in patients with heart failure can be made before further data are available.


 * Oral Hypoglycemic agents: two oral hypoglycemic agents, metformin and thiazolidinediones are considered to be risky in patients with HF. Metformin - one of the most common side effects of metformin is lactic acidosis, which can be fatal in patients with HF.


 * Thiazolidinediones - the biggest risk of using Thiazolidinediones is fluid retention which may cause severe worsening of patients with HF.


 * Antidepressants: Depression is a common finding between patients suffering from HF that is usually related to high mortality rate and bad prognosis of those patients. Limited data are available on the safety and the risks associated with the usage of antidepressants in patients with heart failure. Health care providers should be aware of major cardiovascular events (as HF, MI, Stroke, cardiovascular death ) that is associated with Tricyclic antidepressants (TCAs) and Selective serotonin reuptake inhibitors (SSRIs).


 * Phosphodiesterase inhibitors PDE – The PDE-3 inhibitors as Cilostazol and PDE-4 as Anagrelide should be avoided in patients with HF, because of an increase risk of high-output heart failure and fluid retention that is associated with those drugs.


 * PDE-5 inhibitors such as sildenafil, vardenafil, and tadalafil, are widely used in the management of erectile dysfunction in men. The use of those agents with any form of nitrate therapy is contraindicated because of severe hypotensive effect that can be life threatening. In a trial where sildenafil and placebo were randomly assigned to 34 HF patients, no significant difference of symptomatic hypotension was observed, but HF patients with borderline low blood pressure and/or low volume status are in risk of severe hypotension and should avoid any PDE-5 inhibitors use.


 * Chemotherapy – Cardiotoxic chemotherapeutic agents as Cyclophosphamide, Trastuzumab, Bevacizumab and Anthracyclines, should be avoided in HF patients


 * Tumor Necrosis Factor alpha inhibitors TNF-alpha: New onset or worsening of pre-existing heart failure have been linked to TNF-alpha inhibitors. Infliximab has been specifically contraindicated in doses over 5mg/kg in patients with heart failure.


 * Antihistamines: some second generation antihistamines as terfenadine and astemizole have been reported to cause long QT syndrome and should not be used in HF patients.

Serum potassium should be maintained between 4.0 to 5.0 mEq per liter range, because low potassium level may affect digitalis and antiarrhythmic drugs treatment, while high potassium level can prevent the use of treatments known to prolong life.
 * Serum potassium should be closely monitored in HF patients, in order of preventing either hypokalemia or hyperkalemia, which could greatly affect cardiac excitability and conduction, leading to sudden cardiac death.

Supervision of HF patients with close monitoring of treatment and diet is a very important aspect of the follow-up process in those individuals. Body weight and medications should be closely monitored, because any minor change in those parameters can have a significant effect over symptoms and hospitalization of patients with HF. Patient education is a crucial aspect of the management of HF, patient and family surveillance over any new change of symptoms or body weight is important in allowing early detection of those changes and implementing new treatment strategies to reduce further complications.

==ACC/AHA Guidelines- Antiarrhythmics Recommendation == {{cquote|

Class I
1. Drugs known to adversely affect the clinical status of patients with current or prior symptoms of heart failure and reduced left ventricular ejection fraction (LVEF) should be avoided or withdrawn whenever possible (e.g., nonsteroidal anti-inﬂammatory drugs, most antiarrhythmic drugs, and most calcium channel blocking drugs.      (Level of Evidence: B)}}