Fig. 3. Use-dependent effects on longitudinal (  2A ) and transverse (  2B ) conduction velocities of enflurane in frozen hearts. Data are expressed as the mean. Wash-out values and standard deviation bars are omitted for clarity. A use-dependency was noted at 5 vol% enflurane and at pacing cycle lengths (PCLs) of 250 and 200 ms. θL = longitudinal ventricular conduction velocity (expressed as cm/s);θT = transverse ventricular conduction velocity (expressed as cm/s);‡  P < 0.001  versus baseline.