The Annals of Thoracic Surgery, Vol 35, 500-503, Copyright © 1983 by The Society of Thoracic Surgeons
Fluorocarbon cardioplegia and myocardial protection
GL Hicks, W Arnold and RA DeWall
This study compares myocardial protection using nonoxygenated clear
cardioplegia with oxygen-carrying solutions of blood (PO2, 100 mm Hg) and
fluorocarbon (FC-47 perfluorotributylamine, PO2, 500 mm Hg), all containing
25 mEq/L of potassium chloride. Three groups of dogs, each consisting of 5
animals, were placed on cardiopulmonary bypass, and the aorta of each dog
was cross-clamped for 45 minutes. Hemodynamic and biochemical variables
were measured at baseline and during recovery. Levels of the myocardial
isoenzyme of creatine phosphokinase (CPK-MB) in the coronary sinus were
significantly lower in the fluorocarbon cardioplegia group at 15 minutes of
aortic cross-clamping (p less than 0.01), while both the fluorocarbon and
blood cardioplegia groups demonstrated lower CPK-MB levels at 45 minutes (p
less than 0.001 and p less than 0.05, respectively), compared with the
clear cardioplegia group. The blood and fluorocarbon groups had improved
mean aortic blood pressure (p less than 0.02 and p less than 0.05,
respectively) and left ventricular pressure. At 45 minutes of reperfusion
and recovery, all hemodynamic and enzymatic variables were similar in each
group. We conclude that oxygenated solutions better protect the myocardial
cell, but that further work is needed to determine the most effective
oxygen level for maximum protection with cardioplegia.
