A group of more than 150 cardiologists has issued recommendations for the treatment of chronic heart failure. The recommendations were developed on behalf of a not-for-profit organization called the Advisory Council to Improve Outcomes Nationwide in Heart Failure (ACTION HF). The recommendations are published in the January 21, 1999, issue of the American Journal of Cardiology.
General treatment recommendations advocate the use of a four-drug regimen that includes digitalis, a diuretic, an angiotensin-converting enzyme (ACE) inhibitor and a beta-adrenergic blocker. According to the recommendations, ACE inhibitors and beta blockers are underprescribed for the treatment of chronic heart failure: only about 40 percent of patients receive ACE inhibitors, and only about 5 percent of patients receive beta blockers. Combination therapy is considered to be the optimal approach for most patients with heart failure.
The 38-page report is divided into two parts: part 1 discusses the evaluation of patients with heart failure, and part 2 discusses prevention and management. The following information is excerpted from six tables that provide summaries of recommendations in the report.
General Management Measures
Measures to decrease the risk of new cardiac injury—cessation of smoking; weight reduction in obese patients; control of hypertension, hyperlipidemia and diabetes; and discontinuation of alcohol use.
Measures to maintain fluid balance—restriction of daily intake of salt to 3 g or less and daily measurement of weight to detect early occurrence of fluid retention.
Measures to improve physical conditioning—participation in moderate exercise to prevent or reverse physical deconditioning; do not instruct patients to limit their activity.
Measures to follow in selected patients—control of the ventricular response in patients with atrial fibrillation or other supraventricular tachycardias; anticoagulation in patients with atrial fibrillation or a previous embolic event (and, possibly, other high-risk patients); and coronary revascularization in patients with angina (and, possibly, in patients with ischemic but viable myocardium).
Pharmacologic measures to avoid—do not use antiarrhythmic agents to suppress asymptomatic ventricular arrhythmias, most calcium antagonists and nonsteroidal anti-inflammatory drugs.
Close follow-up is advised to detect early evidence of clinical deterioration. In addition, influenza and pneumococcal immunizations are recommended.
Use of Diuretics
The recommendations state that diuretics should be prescribed for all patients with symptoms of heart failure and evidence of a predisposition to fluid retention. Diuretics are the only reliable means of controlling fluid retention associated with heart failure. Diuretics should not be used alone, however; a diuretic generally should be used in combination with an ACE inhibitor and a beta blocker.
The goal of diuretic therapy is to eliminate symptoms and physical signs of fluid retention, as assessed by jugular venous pressure, peripheral edema, or both. If hypotension or azotemia occurs before symptoms and signs are eliminated, the rapidity of diuresis may be slowed, but diuresis should be maintained until fluid retention is eliminated, as long as the changes in blood pressure and renal function are mild or moderate in severity and do not produce symptoms. Measurement of body weight, preferably daily, is the most useful way to select the diuretic dose and monitor the patient's response to diuretic therapy.
Underdosing of diuretics can lead to fluid retention, which may diminish the response to ACE inhibitors and increase the risk of treatment with beta blockers. Overdosing of diuretics can lead to volume depletion, which may increase the likelihood of hypotension with ACE inhibitors and vasodilators and may increase the risk of renal insufficiency with ACE inhibitors and angiotensin II receptor antagonists.
The recommendations state that diuretic resistance can be overcome by intravenous administration of diuretics, by the use of more than two diuretics in combination or by the short-term use of drugs that increase renal blood flow (e.g., dopamine and dobutamine). Diuretic resistance may be caused by concomitant therapy with non-steroidal anti-inflammatory drugs.
Use of ACE Inhibitors
The recommendations state that all patients with heart failure caused by left ventricular dysfunction should receive an ACE inhibitor unless they are known to be intolerant or to have contraindications to this class of drugs. An ACE inhibitor is generally used with a diuretic in patients who have fluid retention. An ACE inhibitor is also recommended in patients with left ventricular systolic dysfunction but no symptoms of heart failure. Although clinical trials suggest that all ACE inhibitors are likely to exert beneficial effects in heart failure, preference should be given to the target doses of the specific ACE inhibitors evaluated in large-scale studies. ACE inhibitors should generally not be used to stabilize acutely ill patients.
Patients receiving ACE inhibitors should be told that side effects may occur early in therapy but do not generally prevent long-term use, and that symptomatic improvement may not occur for several weeks or months of therapy. Patients should also be informed that ACE inhibitor therapy may reduce the risk of disease progression, even if the symptoms do not respond to treatment.
Use of Beta Blockers
The recommendations state that beta blockers should be used in all patients with stable New York Heart Association class II or class III heart failure caused by left ventricular systolic dysfunction, unless contraindicated. A beta blocker is used in combination with a diuretic and an ACE inhibitor.
As with ACE inhibitor therapy, patients receiving beta blockers should be told that side effects may occur early in therapy but do not generally prevent long-term use. Symptomatic improvement may not occur until after two to three months of therapy. Patients should also be informed that beta blocker therapy may reduce the risk of disease progression even if the symptoms do not respond to treatment.
More data are needed on the effects of beta blockers in patients with unstable disease or class IV symptoms before use of these agents can be recommended for such patients. Beta blockers should not be used as “rescue” therapy in acutely ill patients.
Use of Digitalis
Digoxin is recommended in conjunction with a diuretic, ACE inhibitor and beta blocker in patients with heart failure caused by left ventricular systolic dysfunction. It also is recommended in patients with heart failure and rapid atrial fibrillation, even though beta blockers may be more effective in controlling the ventricular response during exercise.
The recommendations note that there is no evidence to support monitoring of serum digoxin levels as a guide for the appropriate dose. According to the recommendations, digoxin is well tolerated by most patients with heart failure. It is unknown whether long-term digoxin therapy exerts deleterious cardiovascular effects at the doses that are generally in the therapeutic range.
Role of Antiarrhythmic Agents
Class I antiarrhythmic agents should not be used in patients with heart failure, except in the treatment of life-threatening ventricular arrhythmias that are refractory to treatment. The recommendations state that some class III agents, such as amiodarone, do not appear to increase the risk of death in patients with chronic heart failure, and these drugs are preferred over class I agents when used for the treatment of atrial arrhythmias in patients with left ventricular dysfunction. Given its known toxicity and equivocal evidence for efficacy, amiodarone is not recommended for general use to prevent death, including sudden death, in patients with heart failure already treated with drugs that reduce mortality.
The recommendations also point to the need to monitor and correct potassium and magnesium levels, because low levels can cause atrial and ventricular arrhythmias and can alter the efficacy and toxicity of antiarrhythmic interventions.