Each year about 550,000 new patients are diagnosed as having congestive heart failure, which for acutely symptomatic patients is also referred to as acutely decompensated heart failure. The incidence of congestive heart failure is approximately 10 per 1000 for Americans over the age of 65 years. Men and women are affected in equal numbers, and 5-year mortality has been reported to be as high as 50%. Increased longevity increases the likelihood that heart failure will develop as a consequence of pathophysiologic processes that gradually weaken the myocardium and the vascular system. Patients who present to the emergency department with complaints of shortness of breath, dyspnea on exertion, increasing lower extremity edema, and/or worsening fatigue should have heart failure included in the differential diagnosis. Heart failure patients experiencing symptoms consistent with cardiac ischemia, hypoxia, potentially lethal arrhythmias, marked hypertension, or hypotension should be immediately triaged to a critical care area. The approval of nesiritide by the U.S. Food and Drug Administration in 2001 has stimulated the development of revisions in strategies for the emergency department treatment of acute decompensated heart failure patients. The early use of nesiritide, along with topical nitroglycerin and a loop diuretic, may lead to more rapid resolution of these patients' acute symptoms and hemodynamic dysfunction.