The symptoms of heart failure

Chronic heart failure (CHF) and acutely decompensated heart failure (ADHF) are the most frequent hospital diagnoses in industrialized countries. The clinical presentation of heart failure is dominated by two symptoms: dyspnea and fatigue. These symptoms dictate patients' physical capacity and quality of life. Popular clinical classifications of CHF are based on exercise tolerance, ie, on dyspnea after effort and includes the most popular one proposed many decades ago by the New York Heart Association (NYHA). Traditionally, the reduced exercise capacity of HF patients is attributed to the malfunctioning cardiac pump. More recently, "peripheral" factors have been identified that may contribute to the limited exercise capacity associated with CHF. Morphological and functional abnormalities found in both skeletal muscle and respiratory muscles, including muscle atrophy, fiber type changes, reduced mitochondrial enzymes, decreased mitochondrial volume density, and alterations at the vascular/skeletal muscle interface (greater sympathetic vasoconstrictor tone, decreased capillarity, and smaller capillary diameter) may all contribute to dyspnea and fatigue, in addition to or independently from "central" derangements.