HIGH-OUTPUT STATES



If the circulatory system cannot meet a height­ened demand for oxygen, high-output cardiac fail­ure is said to’occur. In high-output states, the heart must pump abnormally large volumes of blood, and the myocardial failure that ensues is similar to that caused by regurgitant valvular lesions. Dis­ease entities associated with high-output heart failure include severe anemia, hyperthyroidism, systemic arteriovenous fistulae and other left-to-right shunts, e.g., patent ductus arteriosus, beri­beri heart disease (vitamin Bi deficiency), and Pag-et’s disease. Increased workloads on the normal heart usually do not result in cardiac failure (e.g.,pregnancy, hepatic and renal disease, pulmonary disease, and obesity); however, if superimposed on pre-existing heart disease, high-output failure can occur in these conditions.
Symptoms and signs of pulmonary and sys­temic congestion are similar to those found in pa­tients with low-output congestive heart failure. Because of the increased stroke volume, de­creased peripheral vascular resistance, and in­creased rate of ejection, the pulses are bounding, with a rapid upstroke and a wide pulse pressure. Physical signs of the underlying process should be sought. Treatment involves the treatment of the etiological disorder.





HIGH-OUTPUT STATES