Table 1.

Cardiac Size and Function of L2^Δ6 Mice

	L2Δ6		WT		ANOVA
					Mutant	Age	Interaction
Age (w)	Adult 25.1±2.3	Aged 39.7±6.5	Adult 28.5±1.7	Aged 37.5±6.5
n	6	6	5	8
IVSd (mm)	0.79±0.09	0.92±0.10	0.60±0.05	0.71±0.06	0.03	0.17	0.92
LVPWd (mm)	0.97±0.05	0.99±0.10	0.70±0.05	0.82±0.05	0.006	0.35	0.5
LVEDd (mm)	3.93±0.18	4.37±0.60	3.70±0.28	3.85±0.22	0.3	0.46	0.72
FS (%)	39.3±4.9*	26.7±6.1*	31.2±3.7	32.5±4.5	0.8	0.31	0.2

Mice were studied at 2 age categories. All measurements were performed at heart rate of 500 to 550 bpm. L2^Δ6 mice tended to have slower heart rate, but that was not statistically significant. There was no apparent difference in the negative chronotropic effect of the anesthesia between mutant and wild‐type mice.

Data are expressed as mean±SEM. FS indicates fractional shortening; IVSd, interventricular septum diameter; L2^Δ6, in‐frame LAMP2 gene exon 6 deletion; LVEDd, left ventricular end‐diastolic diameter; LVPWd, left ventricular posterior wall diameter; and WT, wild‐type.

ANOVA indicates a significant increase in the wall thickness in mutant mice without effect on left ventricular dimension or shortening fraction. There was no significant effect of age or interaction of age with L2^Δ6 mutation.

^*In a post‐hoc analysis, aging was associated with a decrease in the shortening fraction of L2^Δ6 mice (*P<0.01 comparing aged to young L2^Δ6 mice) but no such change was seen in wild‐type mice.