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Detection of myocardial viability based on measurement of sodium content: A 23 Na‐NMR study

2001; Wiley; Volume: 45; Issue: 5 Linguagem: Inglês

10.1002/mrm.1103

1522-2594

Michael P. Horn, Claudia Weidensteiner, Heike Scheffer, Martin Meininger, Mark de Groot, Helga Remkes, Charlotte Dienesch, Karin Przyklenk, Markus von Kienlin, Stefan Neubauer,

Cardiovascular Function and Risk Factors

Abstract MRI of total sodium (Na) content may allow assessment of myocardial viability, but information on Na content in normal myocardium, necrotic/scar tissue, and stunned or hibernating myocardium is lacking. Thus, the aims of the study were to: 1) quantify the temporal changes in myocardial Na content post‐myocardial infarction (MI) in a rat model (Protocol 1); 2) compare Na in normally perfused, hibernating, and stunned canine myocardium (Protocol 2); and 3) determine whether, in buffer‐perfused rat hearts, infarct scar can be differentiated from intact myocardium by 23 Na‐MRI (Protocol 3). In Protocol 1, rats were subjected to LAD ligation. Infarct/scar tissue was excised at control and 1, 3, 7, 28, 56, and 128 days post‐MI ( N = 6–8 each), Na content was determined by 23 Na‐NMR spectroscopy (MRS) and ion chromatography. Na content was persistently increased at all time points post‐MI averaging 306*–160*% of control values (* P < 0.0083 vs. control). In Protocol 2, 23 Na‐MRS of control (baseline), stunned and hibernating samples revealed no difference in Na. In Protocol 3, 23 Na‐MRI revealed a mean increase in signal intensity, to 142 ± 6% of control values, in scar tissue. A threshold of 2 standard deviations of the image intensity allowed determination of infarct size, correlating with histologically determined infarct size ( r = 0.91, P < 0.0001). Magn Reson Med 45:756–764, 2001. © 2001 Wiley‐Liss, Inc.