The Annals of Thoracic Surgery, Vol 33, 434-444, Copyright © 1982 by The Society of Thoracic Surgeons
Pressurized rapid cardioplegia versus administration of exogenous substrate and topical hypothermia
JE Molina, KS Gani and DM Voss
Five hundred fifty-nine patients undergoing aortocoronary operation were
analyzed retrospectively according to the type of myocardial protection
implemented during the period of ischemia. In Group 1 (253 patients), a
rapid method of hypothermic cardioplegia alone was utilized. In Group 2
(306 patients), slower infusion of the same solution with topical
hypothermia was implemented. Cardiac isoenzymes (CPK-MB, LDH1, LDH2, serum
glutamic oxaloacetic transaminase [SGOT]) and myocardial infarct index
(MII) were measured postoperatively for 48 hours. Immediately after
operation, a significant difference was found between Groups 1 and 2 in the
CPK-MB isoenzyme mean value levels--12.1 versus 18.6 IU, p less than
0.01--and MII mean values--5.2 versus 8.1, p less than 0.01. CPK-MB
variances between subgroups receiving two, three, and four grafts were
significantly different in favor of Group 1. Differences were also found in
LDH1, LDH2, total lactic dehydrogenase (LDH), and SGOT: Group 2 levels were
significantly higher than in Group 1. There were ten intraoperative
infarctions in Group 2 and none in Group 1. In 45% of the patients in Group
2, inotropic agents were necessary in the postoperative period versus none
in Group 1. Spontaneous cardiac rhythm following ischemia occurred in 89.7%
of the patients in group 1 versus 29% in Group 2. A method of pressurized
high-flow rapid cardioplegia with intermittent reperfusions alone, seems to
provide adequate protection of the myocardium during ischemia over a slower
low-flow method of infusion combined with topical hypothermia.