Table 1.

Isolated-perfused heart analysis

Group	Histology, n	Ventricular tachycardia			Disorganized conduction
		Spontaneous	Induced	Total (%)
Control	Normal (9)	0	1	1  (11%)	0
Transgenic	Mild (5)	1	2	3  (60%)	1
	Moderate (5)	1	3	4  (80%)	0
	Severe (5)	2	3	5  (100%)	2

This table summarizes the results of the isolated-perfused heart analysis. Control (n = 9) and binary transgenic (n = 15) hearts were optically imaged during the pacing protocol. The occurrence of either spontaneous or inducible ventricular tachycardia was then determined. At the end of the study, hearts were fixed in formalin and sectioned, and the extent of pathology was graded by an observer who was blinded as to genotype status or results of the optical mapping analysis.