Table 2.

Effect of milrinone and cilostazol on action potential duration (APD₉₀), maximal EDR, TDR and incidence of Phase 2 reentrant and polymorphic VT arrhythmias.

	Epi 1 APD90  (ms)	Epi 2 API) 90  (ms)	Endo APD90  (ms)	EDR  (ms)	TDR  (ms)	Phase 2  reentry	Polymorphic  VT
Control	174.7 ± 3.6	173.9 ± 3.3	184.7 ± 3.1	4.8 ± 1.4	7.3 ± 1.1	0/7	0/7
NS5806  5 μM	179.2 ± 1.9	180.6 ± 3.4	183.1 ± 3.5	5.3 ± 0.4	8.7 ± 2.0	1/7	1/7
+Verapamil  2 μM	201.1 ± 8.4*	112.8 ± 13.5†	179.7 ± 4.9	84.9 ± 14.4†	66.9±11.8†	7/7	7/7
+Milrinone  2.5 μM	187.8 ± 3.5	186.5 ± 4.8‡	193.0 ± 4.0	6.5 ± 1.7§	7.5 ±1.3§	1/7	0/7
Wash out Milrinone	219.2 ± 8.5†	145.1 ± 7.6*	189.2 ± 6.9	74.2 ± 13.3†	46.7 ± 9.5†	7/7	6/7
	Epi 1 APD90  (ms)	Epi 2 APD90  (ms)	Endo APD90  (ms)	EDR  (ms)	TDR  (ms)	Phase 2  reentry	Polymorphic  VT
Control	174.7 ± 2.0	170.5 ± 3.1	184.8 ± 3.7	9.1 ± 2.3	11.0 ± 2.3	0/6	0/6
NS5806  5 μM	177.3 ± 3.6	174.1 ± 5.9	187.1 ± 2.4	9.9 ± 3.0	12.1 ± 2.7	0/6	0/6
+Verapamil  2 μM	206.7 ± 9.4*	145.8 ± 9.2*	183.3 ± 7.3	62.5 ± 3.1†	43.3 ± 5.7†	6/6	4/6
+Cilostazol  5 μM	186.0 ± 5.3	191.9 ± 5.3*,‡	183.8 ± 6.4	5.6 ± 2.3§	12.9 ± 4.1‡	0/6	0/6
+Cilostazol  10 μM	185.9 ± 5.3	185.1 ± 5.1‡	183.9 ± 6.4	4.8 ± 1.6§	7.8 ± 2.1§	0/6	0/6
Wash out Cilostazol	210.2 ± 11.2*	135.8 ± 6.4†	188.3 ± 9.9	67.8 ± 15.1†	55.5 ± 11.2†	6/6	4/6

APD₉₀: action potential durations at 90% of repolarization; TDR: transmural dispersion of repolarization; EDR: epicardial dispersion of repolarization. APD₉₀, EDR and TDR are measured in case of single stimulated beat with loss of the AP dome at EPI 2 site but not EPI 1. Results are mean ± S.E.M.

^*p < 0.05 and

^†p < 0.01 vs. control.

^‡p < 0.05 and

^§p < 0.01 vs. NS5806+verapamil combination (Brugada-model). n=7 for milrinone, n=6for cilostazol. Basic cycle length=1000 ms.