A 60-year-old man presents to the emergency department with exertional shortness of breath increasing in severity over the past several days, along with paroxysmal nocturnal dyspnea and orthopnea. He does not have a history of heart failure or previous myocardial infarction. On examination, it was found that he had a third heart sound and an elevated jugular venous pressure. His chest radiograph showed cardiomegaly (Figure 50-1) and his B-type natriuretic peptide (BNP) was elevated at 600 pg/mL. He was diagnosed with heart failure, evaluated for underlying causes including coronary artery disease, and treated initially with an angiotensin-converting enzyme inhibitor (ACEI) and a loop diuretic. Later, he will be started on a β-blocker and an aldosterone receptor antagonist.
Cardiomegaly demonstrated in a posteroanterior (PA) view. The widest part of the heart is greater than 50% of the diameter of the chest. (Reproduced with permission from Heidi Chumley, MD.)
Heart failure (HF) is common and increases with age. HF is a clinical syndrome that has multiple etiologies, all of which lead to a decrease in heart pumping capacity. There are two main types of heart failure: heart failure with reduced ejection fraction (HFrEF), also referred to as systolic HF, and heart failure with preserved ejection fraction (HFpEF) or diastolic HF.1 ACEIs and β-blockers with or without aldosterone antagonists and angiotensin II blockers are the main pharmacologic therapies.
Congestive heart failure (CHF), systolic or diastolic dysfunction.
The prevalence of HF in the community increases with age: 0.7% (45 to 54 years); 1.3% (55 to 64 years); 1.5% (65 to 74 years); and 8.4% (75 years or older).2
In the United States, the prevalence of HF is more than 5.8 million and the annual incidence is approximately 550,000.3
There are race-related differences in the risk of HF, with the prevalence among black men and women about twice that of whites.4
More than 40% of patients in the community with HF have an ejection fraction greater than 50%.5
At age 40 years, the lifetime risk for HF is 21.0% (95% confidence interval [CI] 18.7% to 23.2%) for men and 20.3% (95% CI 18.2% to 22.5%) for women.5
Survival rate is 50% at 5 years after diagnosis.1
ETIOLOGY AND PATHOPHYSIOLOGY
The most common cause of heart failure is ischemia, but heart pumping capacity can decline from several causes (i.e., myocardial infarction or ischemia, hypertension, valvular dysfunction, cardiomyopathy, or infections such as endocarditis or myocarditis).
Cardiac dysfunction activates the adrenergic and renin-angiotensin-aldosterone systems.
These systems provide short-term compensation, but chronic activation leads to myocardial remodeling and eventually worsening of cardiac function.
Norepinephrine, angiotensin II, aldosterone, and ...