Perfluorocarbon supplementation and postischemic cardiac function.
BACKGROUND
During induced ischemia for cardiac surgery inefficient anaerobic energy mechanisms predominate. Sustaining aerobic metabolism with perfluorocarbon-supplemented blood cardioplegia theoretically could lead to improved postischemic recovery. Therefore we studied functional recovery after myocardial ischemia, comparing perflubron (C8F17Br) supplemented blood cardioplegia to standard blood cardioplegia.


METHODS
Nineteen dogs underwent 15 minutes of 37 degrees C global ischemia on cardiopulmonary bypass, followed by 90 minutes of cardioplegic arrest by use of blood cardioplegia with or without perflubron and then 30 minutes of 37 degrees C reperfusion. During ischemia myocardial oxygen tension, temperature, and pH were measured. Postischemic left ventricular recovery was assessed by means of preload recruitable stroke work, exponential end-diastolic stress-strain regression, and preservation of adenosine triphosphate and energy charge.


RESULTS
The addition of perflubron, a new shorter half-life, lecithin-emulsified perfluorocarbon, provided superior myocardial protection when compared with standard blood cardioplegia. This benefit was evidenced by significantly increased recovery of preload recruitable stroke work slope (71% +/- 8% versus 42% +/- 9%), decreased myocardial edema, and enhanced end ischemic myocardial oxygen and pH levels.


CONCLUSIONS
The reliable oxygen delivery system and endothelial-preserving properties of the perfluorocarbons may prove to be an invaluable asset in addition to standard blood cardioplegia in the preservation of postischemic ventricular function. These data support the further investigation of perfluorocarbon-enriched blood cardioplegia.
Mosca
R S
RS
Section of Thoracic Surgery, University of Michigan Medical School, Ann Arbor, USA.
Rohs
T J
TJ
Waterford
R R
RR
Childs
K F
KF
Brunsting
L A
LA
Bolling
S F
SF
D000818:Animals; D002021:Buffers; D002314:Cardioplegic Solutions / Q000494:pharmacology; D004285:Dogs; D005466:Fluorocarbons / Q000494:pharmacology*; D005609:Free Radicals; D018056:Hemorheology / Q000187:drug effects; D017202:Myocardial Ischemia / Q000188:drug therapy*; D015427:Reperfusion Injury / Q000188:drug therapy*; D016277:Ventricular Function, Left / Q000187:drug effects*
D002021:Buffers; D002314:Cardioplegic Solutions; D005466:Fluorocarbons; D005609:Free Radicals