Prognostic value of leucine/phenylalanine ratio as an amino acid profile of heart failure

AbstractHeart failure (HF) causes a hypercatabolic state that enhances the catabolic activity of branched-chain amino acids (BCAA; leucine, isoleucine, and valine) in the heart and skeletal muscles and reduces protein synthesis in the liver. Consequently, free plasma aromatic amino acids (AAA, tyrosine and phenylalanine) are increased. To date, we have reported the prognostic value of the BCAA/AAA ratio (Fischer ’s ratio) in patients with HF. However, the leucine/phenylalanine ratio, which is a simpler index than the Fischer’s ratio, has not been examined. Therefore, the prognostic value of the leucine/phenylalanine ratio in patients with HF was investigated. Overall 157 consecutive patients hospitalize d for worsening HF (81 men, median age 78 years) were enrolled in the study. Plasma amino acid levels were measured when the patients were stabilized at discharge. Cardiac events were defined as a composite of cardiac death and hospitalization for worsening HF. A total of 46 cardiac events occurred during the median follow-up period of 238 (interquartile range 93–365) days. The median leucine/phenylalanine ratio was significantly lower in patients with cardiac events than in those without cardiac events (1.4 vs. 1.8,P <  0.001). The best cutoff value of the leucine/phenylalanine ratio was determined as 1.7 in the receiver operating characteristic (ROC) curve for cardiac events. Following a Kaplan–Meier survival analysis, the low group (leucine/phenylalanine ra...
Source: Heart and Vessels - Category: Cardiology Source Type: research