| Properties | Fast response tissues | Slow response tissues |
| Location | Atria, specialized infranodal conducting system, ventricles, AV bypass tracts | SA and AV nodes, depolarized fast response tissues in which phase 0 depends upon calcium current |
| Passive cellular properties | ||
| Normal resting potential | -80 to -95 mV | -40 to -65 mV |
| Active cellular properties | ||
| Phase 0 current | Sodium | Primarily calcium |
| Phase 0 channel kinetics | Fast | Slow activation; inactivation depends upon voltage and cell calcium concentration |
| Peak overshoot | +20 to +40 mV | -5 to + 20 mV |
| Action potential amplitude | 90 to 135 mV | 30 to 70 mV |
| Properties dependent upon active and passive properties | ||
| Threshold voltage | -60 to -75 mV | -40 to -60 mV |
| Conduction velocity | 0.5 to 5 m/second | 0.01 to 0.1 m/second |
| Conducive to reentry | Only with inactivation of sodium channels with marked slowing of conduction velocity | Present in normal tissue |
| Automaticity | Yes | Yes |
