Effect of coronary occlusion and reperfusion on myocardial blood flow during infarct healing.
Coronary occlusion (CO) of 1 h or longer causes transmural myocardial infarction (MI) in the rabbit. We studied how reperfusion of an infarct affected myocardial blood flow (MBF) acutely and after 3 wk of healing. CO was performed in rabbits for 60 or 180 min (n = 22) followed by reperfusion, and MBF to normal and infarcted zones was determined by radioactive microspheres. In a separate series (n = 23), MBF was measured at 21-25 days post-CO in three groups that had either permanent CO or reperfusion after 60 or 180 min of CO. MBF to the infarct was approximately 8 +/- 3% (+/-SE) of normal MBF (3.8 +/- 0.5 ml.min-1.g-1) during 60-180 min of CO but 3 wk later had increased to 33 +/- 6% of normal MBF (P less than 0.005). Reperfusion after 60 or 180 min of CO resulted in 74 +/- 6% and 41 +/- 5% return of normal MBF, respectively, but 3 wk later, MBF had decreased to 25 +/- 5% (P less than 0.001) and 24 +/- 4% (P less than 0.025) of normal MBF, respectively. Thus after 3 wk of postinfarction healing, MBF to the permanently occluded infarcts increased fourfold, whereas MBF decreased by 50% in the reperfused infarcts so that MBF to the scar tissue was comparable among the three groups and was not influenced by acute post-MI reperfusion.
Connelly
C M
CM
Department of Medicine, Boston University School of Medicine, Massachusetts.
Leppo
J A
JA
Weitzman
P W
PW
Vogel
W M
WM
Apstein
C S
CS
D000818:Animals; D001794:Blood Pressure; D003326:Coronary Circulation; D003327:Coronary Disease / Q000503:physiopathology; D003331:Coronary Vessels / Q000502:physiology*; D006321:Heart / Q000503:physiopathology; D006339:Heart Rate; D008297:Male; D009203:Myocardial Infarction / Q000503:physiopathology*; D015425:Myocardial Reperfusion; D009929:Organ Size; D011817:Rabbits; D014945:Wound Healing