The Annals of Thoracic Surgery, Vol 30, 518-526, Copyright © 1980 by The Society of Thoracic Surgeons
Improved myocardial preservation at 4 degrees C
DK Swanson, JH Dufek and DR Kahn
We tested the ability of various cardiac preservation techniques to
preserve left ventricular function of isolated canine hearts using
preservation temperatures of 4 degrees or 15 degrees C. The four techniques
tested were: (1) topical hypothermia, and hypothermic arrest induced by (2)
perfusion of 1 liter of a modified Collins solution, (3) perfusion of 1
liter of a modified extracellular solution (DKS), or (4) perfusion of 500
ml of blood cardioplegia. Following the cold ischemia period, the hearts
were reperfused with blood in the working heart preparation and tested for
their ability to recover left ventricular function. Hearts preserved 2
hours at 15 degrees C using hypothermia, modified Collins solution, or DKS
solution achieved an average of 60, 73, and 95%, respectively, of baseline
function. Hearts preserved 3 hours at 4 degrees C using topical hypothermia
attained 70% of baseline function, while hearts stored 5 hours at 4 degrees
C using modified Collins solution or DKS solution recovered 83 and 92%,
respectively, of baseline function. Hearts preserved at 4 degrees C
functioned at levels equal to or greater than that of hearts stored at 15
degrees C, even though the hearts preserved at 4 degrees C were stored for
longer periods than those preserved at 15 degrees C. Hearts preserved with
blood cardioplegia for 2 hours at either 4 degrees or 15 degrees C achieved
functions statistically the same as baseline levels during the reperfusion
period. These data show no advantage for preservation temperatures of 15
degrees C compared with 4 degrees C. Our data provide a firm experimental
basis for the clinical use of myocardial preservation temperatures of 4
degrees C, especially when combined with cardioplegia.
