Heart failure represents a broad spectrum of disease caused by impaired ventricular filling and contraction. While incidence has decreased over the past decade, mortality from heart failure has been increasing. The American Heart Association/American College of Cardiology (AHA/ACC) Joint Committee on Clinical Practice Guidelines, with members of the Heart Failure Society of America, published new guidelines on managing the condition, which include recommendations for patients at risk of heart failure and focus on therapy to prevent progression.

Diagnosis

The diagnosis of heart failure is based on the presence of structural heart disease with current or previous symptoms. Clinical signs and symptoms suggestive of heart failure are nonspecific and include jugular venous distention, orthopnea, shortness of breath when bending down, and leg edema.

In patients with suspected or new-onset heart failure as indicated by symptoms, examination, or electrocardiography changes, chest radiography should be performed to evaluate heart size and pulmonary congestion and to rule out other possible causes. B-type natriuretic peptide (BNP) levels should also be measured. If heart failure is suspected, echocardiography is recommended because treatment varies with ejection fraction.

Measurement of BNP levels is most useful for ruling out suspected heart failure because of its high negative predictive value. Although the N-terminal prohormone assay is more accurate, both assays are useful. In a patient with known heart failure, BNP levels change with disease stage, but they are not precise enough to guide therapy. During admission for heart failure, decreasing BNP levels are associated with improved outcomes.

Grading

Heart failure can be characterized by stage, ejection fraction, and functional status (Figure 1). Stages can guide initial treatment of asymptomatic patients. Treatment decisions for documented heart failure can be based on ejection fraction and further adjusted by symptom response.

STAGE

The AHA/ACC guidelines divide heart failure into four stages; the first two describe patients at risk of heart failure and the second two describe patients with heart failure. The condition is characterized by symptoms and structures that highlight the course of the disease.

Stage A is defined by the presence of a risk factor of heart failure without structural changes or symptoms. These patients are at risk due to hypertension, diabetes mellitus, or coronary artery disease, and controlling these risk factors can prevent progression to heart failure.

Patients in stage B (i.e., pre-heart failure) have structural changes in the heart but are currently without signs or symptoms. Affected patients include those with reduced ejection fraction, congenital heart disease, or valvular heart disease with impaired hemodynamics.

Patients in stage C are those with structural changes and previous or current symptoms.

Stage D represents symptomatic heart failure refractory to goal-directed medical therapy.

EJECTION FRACTION

Characterization by left ventricular ejection fraction (LVEF) is primarily relevant in stages C and D. Therapy can be tailored by LVEF ranges.

• LVEF of 50% or more is classified as preserved.

• LVEF of 41% to 49% is classified as mildly reduced. Most patients in this range have a different ejection fraction at the next evaluation.

• LVEF of 40% or less is classified as reduced.

• LVEF that has improved from 40% or less to greater than 40% is classified as improved.

FUNCTIONAL STATUS

The New York Heart Association classification system (https://www.mdcalc.com/calc/3987/new-york-heart-association-nyha-functional-classification-heart-failure) is applicable to stages C and D because it characterizes function according to symptoms. Despite being subjective, changing over time, and having limited reliability, this classification is an independent predictor of mortality.

Treatment Overview by Stage

STAGE A

Sodium-glucose cotransporter-2 (SGLT-2) inhibitors should be prescribed for patients who have diabetes with or at elevated risk of cardiovascular disease to reduce hospitalization by reducing risk of symptomatic heart failure.

STAGE B

Stage B management focuses on guideline-directed medical therapies for the conditions causing structural changes in the heart.

Several medications improve all-cause mortality in heart failure with reduced ejection fraction, regardless of the presence of symptoms.

Angiotensin-converting enzyme (ACE) inhibitors are the cornerstone of treatment for patients in stage B to reduce progression to symptomatic heart failure and reduce mortality. An angiotensin receptor blocker (ARB) can be used in patients with a recent myocardial infarction who cannot tolerate an ACE inhibitor.