Table 1.

Time Profile of Myocardial T2 Relaxation in the Ischemic Porcine Myocardium During the First Week After Different I/R Protocols and Cardioprotective Strategies

T2 Relaxation Time, ms
BaselineR-120 minR-24 hR-Day 4R-Day 7
40-min I/R (controls)46.5 (3.0)74.8 (14.4)46.7 (4.9)66.4 (8.3)78.9 (11.7)
40-min I/R+PostC43.1 (4.1)73.4 (8.8)46.1 (2.5)72.5 (17.0)76.7 (16.8)
PreC+40-min I/R43.1 (1.0)62.5 (2.8)*49.1 (1.2)59.2 (10.8)*57.6 (10.3)*
20-min I/R46.6 (2.0)58.3 (1.5)*49.9 (1.9)50.1 (3.1)*48.7 (1.5)*
  • Values are mean (SD). No significant differences were found between groups at baseline. A bimodal T2 time course was observed for all 40-min I/R pigs, with no significant differences detected between 40-min I/R and 40-min I/R+PostC. In contrast, PreC blunted both T2 peaks, whereas after 20-min I/R, the first peak was blunted and the second, absent. I/R indicates ischemia/reperfusion; PostC, postconditioning; and PreC, preconditioning.

  • * Statistically significant differences (P<0.05) compared with the same time point in the 40-min I/R (control) group. P value is adjusted for multiple comparisons among groups for each time point.