Abstract: Essential amino acid supplementation (EAS) may counteract hypercatabolic states, such as chronic heart failure (CHF). This pilot study investigated whether EAS could improve quality of life (QoL), cardiac function and exercise tolerance in patients (pts) with stable CHF on optimal medical treatment (OMT). We enrolled 27 pts (21 males) with ejection fraction (EF) <35% and on OMT with no changes within the previous 6 months. EAS, composed of leu (1,250 mg), lys (650 mg), ile (625 mg), val (625 mg), thr (350 mg), cys (150 mg), his (150 mg), phe (100 mg), met (50 mg), t4 (30 mg), trp (20 mg), B1 (0.15 mg) and B6 (0.15 mg) vitamins, was given twice a day for 3 months. At baseline and after 3 months, we evaluated symptoms with NYHA classification, LVD36 questionnaire and QoL scale; cardiac function by echocardiography and exercise tolerance (modified Bruce protocol); pro-BNP, renal function, glucose and troponin. We observed a significant reduction of end-systolic and diastolic volumes (ESV 121.6 ± 63.08 vs. 106.82 ± 50.1 mL, p = 0.018; EDV 169.1 ± 75.3 vs. 150 ± 67.5 mL, p < 0.02), an increase of EF (29.8 ± 5.7 vs. 35.4 ± 5.8%, p < 0.001) and of cardiac output (5.58 ± 1.57 vs. 6.07 ± 1.66 L/min; p = 0.015). We assisted a no significant trend toward reduction in mitral regurgitation (p = 0.3). EAS improved QoL (NYHA p < 0.001; LVD36 14.1 ± 7.2 vs. 12.2 ± 6.9, p = 0.015; QoL scale 62.4 ± 12.5 vs. 74 ± 9.7%, p < 0.001); exercise tolerance (stage 3.24 ± 1.3 vs. 3.57 ± 1.3, p = 0.016; METS 6.6 ± 3.4 vs. 7.1 ± 3.3, p = 0.18; Minutes 8.1 ± 4.29 vs. 8.7 ± 3.94, p = 0.055). No changes in glucose, creatinine, cholesterol, troponin and a no significant trend toward reduction of pro-BNP was observed (1,077.4 ± 530.3 vs. 851.6 ± 315.1 ng/l, p = 0.3). No pts showed adverse effects. After 3 months, EAS significantly improves cardiac function, QoL and exercise tolerance in stable CHF pts.
