TABLE 1.

Effects of Procainamide and Sotalol on Restitution Slope and Dispersion of Refractoriness

	Procainamide-First Group (n = 6)			Sotalol-First Group (n = 6)
	Baseline	Procainamide	Combination	Baseline	Sotalol	Combination
Slope	1.15 ± 0.37	0.94 ± 0.38	0.75 ± 0.29**†	1.11 ± 0.17	0.93 ± 0.18**	0.81 ± 0.10**†
ARI (ms)	190	198**	200**	187	194**	197**
SD (ms)	8.2	7.4	7.6	8.1	5.6**	6.0**
CV (%)	4.3	3.7	3.8	4.7	2.9**	3.1**

^*P < 0.05,

^**P < 0.01 compared to baseline,

^†P < 0.05, compared to monotherapy.

Slope is the maximum slope of the restitution curve; ARI, SD, CV are at a pacing cycle length of 300 ms.