FGF23 and hydrops fetalis: In patients with acute MI and concomitant HF, however, FGF23 levels outperformed GRACE score in risk prediction with a fair AUC value of 0.78 (95%CI 0.61–0.95) and an overall predictive accuracy of 93.9% compared with an AUC value of 0.70 (95%CI 0.46–0.94) and an overall predictive accuracy of 91.9% for GRACE score.