Figure 1.

Etiologies and stages of right ventricular failure (RVF). (A) RVF occurs as a consequence of alterations in preload, changes in mechanics and/or decreases in contractility, or increases in afterload. (B) Classification of RVF according to stages of development in keeping with the recent classification of the American College of Cardiology Foundation/American Heart Association Task Force for Heart Failure (298, 299). Note that stages are not static and that stages C and D are potentially reversible with normalization or significant decrease in pulmonary vascular resistance (e.g., after pulmonary endarterectomy or lung transplantation) (300, 301). Symptomatic RVF (stage C) is usually managed pharmacologically, whereas refractory RVF (stage D) often requires specialized interventional or surgical measures. Preventive measures may be applied at any of the different stages of RVF. Decompensation may occur at any stage. (C) Cycle of acute on chronic decompensation of RVF. Acute decompensation is usually provoked by one or more precipitating factors (e.g., infection, pulmonary embolism, bleeding disorders) or by progression of the underlying disease (112). Patients frequently deteriorate and enter a vicious cycle of hypotension, ischemia, and decreased pump function or may stabilize and revert to more or less stable chronic RVF. However, mortality after hospital discharge remains high (35% at 12 mo [112]). PAH = pulmonary arterial hypertension; RHF = right heart failure.