Prognostic significance of cerebral metabolic abnormalities in patients with congestive heart failure

Background - Cerebral metabolic abnormalities were proposed as a potential marker of disease severity in congestive heart failure (CHF), but their prognostic significance remains uncertain. Methods and Results - We investigated the prognostic value of cerebral metabolic abnormalities in 130 consecutive patients with advanced CHF (100 men aged 42.6 +/- 11.9 years; left ventricular ejection fraction, 22.2 +/-6.2%). Proton magnetic resonance spectroscopy data were obtained from localized regions (approximate to8 mt) of the occipital gray matter and the parietal white matter. The primary end point was the occurrence of death after the proton magnetic resonance spectroscopy. During follow-up (18.5 +/- 14.4 months), 21 patients died and 15 underwent urgent heart transplantation. In the Cox proportional model, occipital metabolites (N-acetylaspartate, creatine, choline, and myoinositol), parietal N-acetylaspartate level, and the duration of CHF symptoms (> 12 months) were validated as univariate predictors of death. In multivariate Cox analyses, however, the occipital N-acetylaspartate level was an independent predictor of death (hazard ratio, 0.52; 95% CI, 0.41 to 0.67; P <0.001), An analysis with respect to the combined end point of death or urgent transplantation showed similar results. The best cutoff value (9.0 mmol/kg) for occipital N-acetylaspartate level had 75% sensitivity and 67% specificity to predict mortality. Conclusions - The occipital N-acetylaspartate level is a powerful and independent predictor of CHF mortality, suggesting that cerebral metabolic abnormalities may be used as a new prognostic marker in the assessment of patients with CHF.