The Annals of Thoracic Surgery, Vol 37, 222-228, Copyright © 1984 by The Society of Thoracic Surgeons
Protective effect of an asanguineous reperfusion solution on myocardial performance following cardioplegic arrest
P Menasche, C Grousset, G de Boccard and A Piwnica
This study assesses whether an appropriately designed asanguineous initial
reperfusate effectively reduces the reperfusion injury following prolonged
global ischemia and improves the recovery of cardiac performance after
cardioplegic arrest. Forty-eight isolated perfused working rat hearts
underwent two hours of hypothermic (15 degrees to 18 degrees C) ischemic
arrest followed by 30 minutes of normothermic reperfusion. During ischemic
injury, multidose cardioplegia was delivered at 30-minute intervals. The
reperfusion solution under study was infused during the last 3 minutes of
ischemia, just prior to release of the aortic clamp. The usual hemodynamic
variables of this preparation (heart rate, aortic pressure, aortic flow,
coronary flow, and stroke volume) were serially recorded and expressed as
percent of recovery of control values. The influence of the concentration
of Ca2+, pH, and buffer was more specifically investigated. A reperfusate
containing 1 mM of Ca2+ was found to result in higher postischemic
hemodynamic values than a Ca2+-poor (0.25 mM) reperfusate. The best
functional recovery was provided by an alkalotic (pH 7.70 at 28 degrees C),
glutamate-enriched initial reperfusate, which, by 30 minutes of
reperfusion, yielded a 93.5 +/- 2.3% recovery of aortic flow versus 83.6
+/- 1.8% in the control group receiving unmodified reperfusion (p less than
0.01). We conclude that an appropriate composition of the initial
reperfusate can improve the recovery of cardiac function significantly
following two hours of cardioplegic arrest and that such an improvement can
be achieved by an asanguineous reperfusate provided its composition is
properly designed with respect to electrolytes, pH, and substrates.
