Manganese-Enhanced T₁ Mapping in the Myocardium of Normal and Infarcted Hearts

Table 1

Effect of diltiazem on manganese-induced T₁ shortening.

Time point (minutes)	Baseline T1 (ms)	Mean T1 shortening (ms)
		5	20	40	60
MnCl2 + saline	1286 ± 42	366 ± 72	382 ± 72	389 ± 67	351 ± 35
MnCl2 + diltiazem ()	1180 ± 93	290 ± 52	288 ± 71	276 ± 56	274 ± 63
EVP1001-1 + saline	1265 ± 94	354 ± 91	397 ± 73	352 ± 54	383 ± 87
EVP1001-1 + diltiazem	1375 ± 38	209 ± 27	225 ± 57	211 ± 49	226 ± 40
Mangafodipir + saline	1366 ± 94	142 ± 52	178 ± 59	206 ± 53	220 ± 61
Mangafodipir + diltiazem	1219 ± 69	96 ± 34	128 ± 42	158 ± 66	177 ± 24

Healthy rats (group sizes unless otherwise stated) administered MnCl₂ (22 μmol/kg), EVP1001-1 (22 μmol/kg), or mangafodipir (44 μmol/kg) over 3-4 min with simultaneous administration of 0.9% saline or diltiazem (100–200 µmol/kg/min) infusion. Note the approximate 30% reduction in mean myocardial T₁ values at each time point, but that there is greater discrimination between the diltiazem and saline infused rats due to the superior T₁ shortening with EVP1001-1. Post hoc Bonferroni multiple comparisons (manganese agent + saline; manganese agent + diltiazem). Significance at each time point as compared with saline control is indicated by asterisk.