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LEARNING OBJECTIVES
Upon completion of the chapter, the reader will be able to:
Differentiate between the common underlying etiologies of heart failure (HF), including ischemic, nonischemic, and idiopathic causes.
Describe the pathophysiology of HF as it relates to neurohormonal activation of the renin-angiotensin-aldosterone system and the sympathetic nervous system.
Identify signs and symptoms of HF and classify a given patient by New York Heart Association Functional Classification and American College of Cardiology/American Heart Association Heart Failure Staging.
Describe the goals of therapy for a patient with acute or chronic HF.
Develop a nonpharmacologic treatment plan that includes patient education for managing HF.
Develop a specific evidence-based pharmacologic treatment plan for a patient with acute or chronic HF based on disease severity and symptoms.
Formulate a monitoring plan for the nonpharmacologic and pharmacologic treatment of a patient with HF.
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Heart failure (HF) is defined as the inadequate ability of the heart to pump enough blood to meet the blood flow and metabolic demands of the body.1 More commonly, HF is a result of low cardiac output (CO) secondary to impaired cardiac function. High-output HF is characterized by an inordinate increase in the body’s metabolic demands that outpaces an increase in CO of a generally normally functioning heart. The term heart failure refers to low-output HF for the purposes of this chapter.
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HF results from any structural or functional cardiac disorder that impairs the ability of the ventricle to fill with or eject blood, and can be classified based on the phase of the cardiac cycle leading to impaired ventricular function.1 A normal cardiac cycle depends on two components: systole and diastole. Expulsion of blood occurs during systole, or contraction of the ventricles; diastole relates to filling of the ventricles. Ejection fraction (EF) is the fraction of the volume present at the end of diastole that is pushed into the aorta during systole. Abnormal ventricular filling (diastolic dysfunction) and/or ventricular contraction (systolic dysfunction) can result in similar decrease in CO and cause HF symptoms. HF is commonly associated with evidence of left ventricular (LV) systolic dysfunction (evidenced by a reduced EF, or left ventricular ejection fraction [LVEF] ≤ 40% [0.40]), and when accompanied by symptoms is also known as HF with reduced ejection fraction, or HFrEF. HF can occur with or without a component of diastolic dysfunction which coexists in up to two-thirds of patients. Isolated diastolic dysfunction, occurring in approximately one-third to one-half of HF patients, is diagnosed when a patient exhibits impaired ventricular filling without accompanying HF symptoms but normal systolic function, defined as LVEF 50% (0.50) or greater. When isolated diastolic dysfunction occurs with symptoms of HF, this is referred to as HF with preserved ejection fraction (HFpEF). Long-standing hypertension is the leading cause of HFpEF. Patients with ...