Page 2 - The 5-Minute Clinical Consult 2021 29th Edition

HEART FAILURE, CHRONIC
Jeffrey A. Shih, MD Youssef Rahban, MD

BASICS

DESCRIPTION
Heart failure (HF) is the condition resulting from inability of the heart to fill and/or pump
blood sufficiently to meet tissue metabolic needs. Alternatively, HF may occur when adequate
cardiac output can be achieved only at the expense of elevated filling pressures. It is the
principal complication of heart disease. For acute HF, see “Heart Failure, Acutely
Decompensated.”
HF is the preferred term over congestive HF because patients are not always congested (fluid
overloaded).
HF may involve the left heart, the right heart, or be biventricular.
The New York Heart Association (NYHA) classification is a subjective grading scale used for
classifying a patient’s functional status: NYHA I: asymptomatic; NYHA II: symptomatic with
moderate exertion; NYHA III: symptomatic with mild exertion and may limit activities of
daily living; NYHA IV: symptomatic at rest.
The American Heart Association (AHA) and American College of Cardiology (ACC) stages is
a system to delineate the progression of HF: Stage A: patients at risk for HF, no structural
disease; Stage B: structural disease, no HF symptoms; Stage C: structural disease, HF
symptoms; Stage D: end-stage HF disease.

EPIDEMIOLOGY
HF accounts for close to 1 million hospitalizations a year with 25% readmitted within 30 days.
The annual direct and indirect cost of HF in the United States is ~$34.4 billion.
Incidence
In the United States, 550,000 new cases diagnosed annually with >250,000 deaths per year.

Prevalence
An estimated 23 million individuals have HF worldwide. ~6.5 million people in the United
States have HF; <1% in those age <50 years, increasing to 10% of those age >80 years
Primarily a disease of the elderly; 75% of hospital admissions for HF are for persons >65 years
of age.

ETIOLOGY AND PATHOPHYSIOLOGY
Two physiologic components explain most of the clinical findings of HF and result in
classifications in four general categories:
HF with reduced ejection fraction (HFrEF) or systolic HF: an inotropic abnormality, often due
to myocardial infarction (MI) or dilated cardiomyopathy (CM), resulting in diminished
systolic emptying (ejection fraction [EF] ≤40%)
HF with preserved ejection fraction (HFpEF) or diastolic HF: a compliance abnormality, often
due to hypertensive CM, in which the ventricular relaxation is impaired (EF ≥50%)
Borderline HFpEF (EF 41–49%): mild systolic dysfunction but clinically behaves like HFpEF
Improved HFpEF (EF >40%): previously HFrEF but with improvement in systolic function