Chronic heart failure (HF) is the most costly cardiovascular disorder in the United States.¹ This significant health problem, affecting 4.9 million Americans, accounts for the most frequent hospitalization for persons over 65 years of age, and for greater than 875,000 admissions yearly.²

The financial expenditures for the treatment of HF exceeded $20 billion in 1998.³ The disease is expected to increase in prevalence as the population continues to age.

The guidelines for the evaluation and management of HF were published in 1995 by the American College of Cardiology (ACC) and the American Heart Association (AHA). These documents provide guidelines supported by evidence-based data and expert recommendations to assist the practitioner in her clinical practice. An emergence of more clinical data prompted a revision of these guidelines in 2001.⁴

This article will review the current published recommendations for the approach, evaluation and management of chronic HF. These recommendations are categorized by specific stages, which are based on evidence identified through comprehensive literature searches. The stages refer to data from multiple randomized clinical trials, nonrandomized trials and consensus opinion from experts.

All recommendations follow the same format of previous ACC/AHA guidelines published. These particular guidelines focus on the adult with chronic HF rather than acute HF management.

Heart Failure

HF is a clinical syndrome that results from a structural or functional cardiac abnormality that impairs the ability of the ventricles to fill and eject blood. These abnormalities prevent the heart from supplying the organs with adequate amounts of blood. Such abnormalities can result from disorders affecting the myocardium, pericardium, heart valves and great vessels.

The majority of patients with HF have symptoms resulting from decreased left ventricular systolic function. Coronary artery disease is the underlying cause for the HF in two-thirds of this group.⁴ The nonischemic patient with impaired left ventricular function may have an identifiable cause such as hypertension, thyroid disease, alcohol use, valvular heart disease, myocarditis or an unknown etiology (idiopathic dilated cardiomyopathy).

The most notable manifestations of HF are dyspnea and fatigue that impact exercise tolerance, and fluid retention that leads to pulmonary and/or peripheral edema. Some patients may have exercise intolerance without fluid retention, while others can have fluid retention with few symptoms of dyspnea. As a result of this variability, the term heart failure is preferred over "congestive" heart failure.

NYHA Classification

The New York Heart Association (NYHA) functional classification is commonly used to quantify the functional limitation of a patient. The classifications are numbered 1-4 and are determined by the level of exertion needed to produce symptoms.

Class I = normal

Class II = symptomatic with ordinary exertion

Class III = symptomatic with mild activity

Class IV = symptomatic at rest

This information has been used to help determine appropriate HF treatment for the level of symptoms the patient manifests. This system has been recognized for its limitations due to the subjectivity of the physician and/or the patient, and fluctuation in condition leading to treatment that did not change over the classes or consider disease progression.

Ventricular Dysfunction

The relationship between the level of functional limitation and the severity of ventricular dysfunction is not well understood. A patient with severe left ventricular dysfunction may be asymptomatic compared with a patient with less ventricular dysfunction.

Myocardial failure leading to HF is the result of a progressive process called remodeling by which mechanical, neurohormonal and possibly genetic factors alter the shape, size and function of the ventricle. In the case of left ventricular dysfunction, insult to the myocardium may progress despite evidence of any further insult. This remodeling process leads to changes in the geometry of the left ventricle, which dilates, hypertrophies, and becomes more spherical in shape.

This process generally precedes the development of symptoms and continues after symptoms are noted. There may be an advancement of this process leading to worsening of symptoms despite medical treatment.

This remodeling process and progression of the disease has prompted the ACC/AHA committee on HF guidelines to reevaluate its suggestions. The focus of the guidelines has shifted to prevention and more aggressive treatment, regardless of symptoms. The new guidelines break down the evolution and progression of HF into four stages (Fig. 1).

This aggressive approach to HF should retard or slow the progression of the remodeling process, thereby decreasing the morbidity and mortality of HF.

Assessment of the Patient

Patients with heart failure are commonly identified during a medical evaluation for symptoms, or as an incidental finding of decreased left ventricular function. The initial step in the evaluation process is the compilation of the patient's personal health history, including information about the family, and a physical examination.

The most useful diagnostic test in the evaluation is the two-dimensional echocardiogram with Doppler flow studies. Other diagnostic tests that will assist diagnosis may include but are not limited to electrocardiogram, lab work, stress testing, coronary angiography and chest radiogram.

The goal of this evaluation is to determine the nature and cause of the cardiac disorder that has resulted in HF. This information, along with the ongoing clinical assessment of the patient at each visit, helps the practitioner determine the patient's HF stage. It also helps her select the appropriate treatment.

Treatment in Stage A

Patients in stage A are at high risk of developing left ventricular dysfunction and HF but display no evidence or symptoms of structural heart disease. The modification and in some cases the cessation of several risk factors can slow or retard the progression of the disease process. Early and ongoing interventions at stages A and B will have a significant impact on the prevalence of HF.

Risk factors involved include hypertension, hyperlipidemia, diabetes, coronary disease, family history, smoking, alcohol consumption and use of cardiotoxic drugs. Risk reduction includes patient education with strong advice for the cessation of smoking, limiting alcohol consumption and avoidance of illicit drugs such as cocaine.

In hypertension the elevated systolic and/or diastolic pressures should be lowered in accordance with the recommendations in published guidelines.⁵ Target blood pressure levels are lower for patients with cardiovascular risk factors such as diabetes. An antihypertensive regimen usually includes a combination of drugs. The drugs preferred for hypertension that also benefit HF include angiotensin-converting enzyme (ACE) inhibitors, beta-blockers and diuretics.

The diabetic patient should have glucose control, and studies have demonstrated the positive effect in reducing end-organ damage with the initiation of ACE inhibitor therapy. The aggressive treatment of hyperlipidemia is recommended in accordance with the current guidelines.⁶ The use of ACE inhibition is recommended in patients with cardiovascular risk factors such as atherosclerotic vascular disease, diabetes and hypertension.

Patients receiving treatment with cardiotoxic drugs such as chemotherapeutic agents are at risk for HF and require close monitoring. Also recommended is the identification and management of other conditions that may impact on the heart such as thyroid disease or tachyarrhythmias.

Treatment in Stage B

The patients with structural cardiac disease who are asymptomatic are identified as the stage B group. These patients have structural disease from previous myocardial infarction, ventricular hypertrophy secondary to chronic hypertension, decreased left ventricular function, dilatation, left bundle branch block and asymptomatic valvular disease.

This patient population is at an increased risk for the progression of the remodeling process and development of HF symptoms. The treatment recommendations include all measures under stage A with an emphasis on the utilization of ACE inhibitor and beta-blocker therapy, regardless of the ejection fraction.

The continued management of the risk factors noted previously should be followed. Patients with hemodynamically significant valvular stenosis or regurgitation should be considered for repair or replacement.

Treatment in Stage C

Patients that have structural cardiac disease with current or prior symptoms are recognized as group C. These patients are recommended to receive the same treatment therapy as stage A and B groups. While all of these patients need ongoing education, patients in the stage C group with HF symptoms require close surveillance and follow-up.

Noncompliance with their medication regimen or diet can impact the patient's clinical condition and functional ability. General measures recommended include moderate sodium restriction, monitoring of weight, immunizations with influenza and pneumococcal vaccines, and moderate physical exercise.

Drug classes that should be avoided due to worsening of HF symptoms include antiarrhythmic agents, calcium channel blockers and nonsteroidal anti-inflammatory drugs.

The patients in stage C are routinely managed with the addition of diuretics and lanoxin to ACE inhibitor and beta-blocker therapy. These drugs have demonstrated their effectiveness in clinical studies and are now a mainstay in therapy (Fig. 2). There are additional interventions that have been effective in limited clinical trials, including cardiac resynchronization therapy, aldosterone inhihibitor, angiotensin receptor blockers and exercise training.

There are several clinical trials in progress evaluating the effectiveness of various drugs and interventions that are not recommended at this time. Surgical revascularization and valvular repair and replacement are also treatment options in selected patients.

Treatment in Stage D

Patients with refractory advanced HF, the stage D group, are symptomatic at rest or with minimal exertion despite optimal medical therapy. These patients have end-stage HF and need to be considered for specialized treatment such as mechanical circulatory support, continuous inotropic therapy, cardiac transplantation or hospice care. Their treatment regimen is strongly influenced by monitoring fluid retention. The drug therapy recommended in previous stages is continued but may be less tolerated due to hypotension and renal insufficiency.

Cardiac transplantation is the only established surgical procedure indicated. This option requires chronic immunosuppression therapy and has risks of rejection and infection. Candidates are limited to less than 70 years, with minimal comorbidities, and the absence of life-threatening disease other than cardiac. Alternative destination therapy with surgical and mechanical support devices are under investigation. As the options for therapy become exhausted, the recommendation for hospice care is considered for the relief of symptoms.

Other Guidelines

There is a population of patients clinically in HF with normal systolic function on echocardiogram. This disorder is not fully understood and is likely the result of a ventricular filling impairment, otherwise known as diastolic heart failure.

This problem is common among the elderly, particularly women and patients with chronic hypertension. In contrast to systolic dysfunction, there are limited clinical studies available for recommendations. However, the focus on prevention of HF risk factors such as hypertension is addressed.

The guidelines also address the treatment of a special population of patients with multiple comorbid conditions that may contribute to HF from cardiovascular and noncardiovascular disorders. The recommendation for this group is to identify and appropriately manage each of the comorbid conditions to limit their influence on HF.

Conclusion

As more clinical data become available, these guidelines will be revised further. Despite the availability of these evidence-based guidelines, a significant number of patients are still inadequately treated. And now, with a preventive focus built into the treatment guidelines, an even broader group of patients needs to receive treatment.

The presence of published guidelines for several disorders such as HF, hypertension and hyperlipidemia provide the health care practitoner with the current knowledge and recommendations supported by clinical data.^4,5,6 We as health care practitioners are responsible for integrating this into our daily practice to provide patients with the most effective treatment.

Donna Chojnowski is a heart transplant nurse coordinator for the Hospital of the University of Pennsylvania Heart Failure Transplant Program, Philadelphia.