SCN5A and cardiomyopathy: These observations are consistent with the intrinsic characteristics of each model, since the Scn5a+/− line is a model of channelopathy (arrhythmia only) whereas the LmnaH222P/H222P line is a model of cardiomyopathy which seems more arrhythmic than WT mice but less than Scn5a+/− mice.