Approximately 400,000 patients in the United States are newly diagnosed with congestive heart failure each year. The vast majority of these patients will not survive 5 years. Symptoms that indicate a decline in patient status often go unrecognized by providers. Early identification of insidious changes and prompt intervention can improve cardiac function and decrease the incidence of acute episodes and repeated hospitalizations. Nurse practitioners in the primary care setting are often called upon to manage these patients. By understanding the physiological changes as they occur and the underlying etiology, management is enhanced.