Myocardial flow reserve parametric map, assessed by first-pass MRI compartmental analysis at the chronic stage of infarction

Regional myocardial flow and flow reserve (MFR) were assessed by compartmen tal analysis of Gd-enhanced MRI first-pass data in 7 patients with atypical chest pain, and In 15 patients with previous transmural myocardial infarct ion. The FE product (Flow X Extraction coefficient), derived from the modif ied Kety equation, was measured in regions corresponding to the Tetrofosmin e-SPECT fixed defect and In remote normal regions. The FE product at rest a nd hyperemic FE product were similar in healed revascularized tissues (70.5 +/- 15.6 and 112.5 +/- 19.5ml/mn/100g, respectively) and in normal myocard ium. (76.2 +/- 18.3 and 142.2 +/- 33.0, respectively). In contrast, the FE index (48.8 +/- 15.2 and 60.7 +/- 18.0, respectively, P < 0.01 versus the t wo previous groups) and the MFR (1.27 +/- 0.20 vs. 1.91 +/- 0.29 in normal regions) were reduced in healed fibrotic tissues when the Infarct-related a rtery remained occluded. Myocardial flow reserve maps allowed correct Ident ification of regions corresponding to an occluded infarct-related artery. ( C) 2001 Wiley-Liss, Inc.