ABSTRACT
HEART FAILURE Classically, heart failure has been defined as the pathophysiologic state in which an abnormality of cardiac function is responsible for failure of the heart to pump blood at a rate commensurate with the requirements of the metabolizing tissues, or to do so only when filling pressures are excessively increased. Not all patients with ventricular dysfunction have the clinical syndrome of heart failure. In recognition of the continuous and progressive nature of ventricular dysfunction, heart failure is now divided into four stages: stage A patients have risk factors for heart failure (hypertension, coronary heart disease, diabetes, obesity) but normal ventricular function and no heart failure symptoms; stage B patients have structural abnormality but no heart failure symptoms; stage C patients have ventricular dysfunction and symptoms of inadequate cardiac output (exercise intolerance) and/or fluid overload (congestion); stage D patients have advanced symptoms and severe disability. The stages are associated with increasing morbidity and mortality (Fig. 1).
