Fischer’s ratio predicts cardiac events in HF patients

Fischer’s ratio (FR)―the ratio of branched-chain amino acids (BCAA) to aromatic amino acids (AAA)―appears to be helpful in predicting cardiac events in patients with heart failure (HF), a recent study has found.

Researchers enrolled 157 consecutive patients (mean age, 75 years; 62 percent male) admitted for worsening HF. Plasma concentrations of BCAA (total isoleucine, leucine, and valine) and AAA (total phenylalanine and tyrosine) were measured at discharge. The study outcome was the occurrence of cardiac events, defined as a composite of cardiac death and hospitalization.

The mean plasma BCAA and AAA concentrations were 419.8 and 141.3 nmol/mL, respectively, and the resulting mean FR was 3.0.

Over a mean follow-up period of 221±135 days, a total of 46 cardiac events occurred, including 14 cardiac deaths and 32 hospitalizations due to worsening HF. Kaplan-Meier survival analysis revealed that cardiac events occurred significantly more commonly in low-FR participants (p<0.001).

Receiver operating characteristic curve analysis showed that an optimal cut-off value of 2.9, with a 70-percent sensitivity and 69-percent specificity (area under the curve, 0.720; p<0.001).

Cox proportional hazard regression analysis revealed that FR below the cut-off was significant and independent prognostic factor for scores in the Get With The Guidelines-Heart Failure tool (hazard ratio, 1.04, 95 percent confidence interval, 1.00–1.09; p=0.022). This remained true even after the addition of different confounders to the model.

“[F]urther studies, with larger numbers of patients in multiple centers, are required to validate our results,” said the researchers.