Table 2.

Propagation of simulated premature ventricular complexes (PVCs) in several different myocardial fibers.

Fiber ID	Bcl (ms)	NZ/BZ composition	β-Adrenergic stimulation	Shortest CI with propagating S2 (ms)
A	300	NZ-BZ-NZ	0	176
B	300	NZ only	0	181
C	400	NZ-BZ-NZ	0	190
D	400	NZ only	0	184
E	300	NZ-BZ-NZ	100	180

Bcl gives the pre-pacing cycle length (S1), NZ/BZ composition determines whether the fiber contains a BZ zone or is entirely composed of NZ cells, β-adrenergic receptor stimulation gives the relative concentration of β-agonist used, and shortest propagating S2 is the interval between the previous activation of the center of the fiber and the activation obtained using the S2 stimulus, representing the cells’ refractory period.