Fig. 4From: Effect of polypharmacy on plasma bepridil concentration in patients with heart failure: a multicenter retrospective studyCorrelation of the number of concomitant drugs used with the C/D ratio of bepridil in patients with HF. Each column represents the mean ± standard deviation. **p < 0.01 and ***p < 0.001 compared with the number of concomitant drugs < 6. NS, not significant; C/D, concentration-to-dose ratioBack to article page