Dynamic water changes in excised rat myocardium assessed by continuous distribution of T1 and T2

Abstract

Ischemic changes in excised rat myocardium were followed by series of T1 or T2 measurements from 1 to 60 min after isolated perfusion cessation, and the influence of manganese enhancement was investigated. An inverse Laplace transformation (ILT) of T1 or T 2 data was used to resolve the number, time constants, and fractions of tissue water components in a continuous distribution. For T1 distributions, one single tissue component ∼900 ms was significantly shortened and dispersed by manganese enhancement (25 and 200 μM MnCl 2). For T2 distributions, three tissue components (∼30, ∼100, and ∼350 ms) were obtained initially. The two shortest components merged after ∼10 min to one component (∼40 ms). Both T 1 and T2 tissue components became shorter with time. In particular, the T2 distribution dynamics might be compatible with complex sequential changes in tissue water fractions during ischemia. © 2007 Wiley-Liss, Inc.