The Journal of Thoracic and Cardiovascular Surgery, Vol 70, 458-465, Copyright © 1975 by The American Association for Thoracic Surgery and The Western Thoracic Surgical Association
Effects of myocardial ischemia on ventricular compliance. Protective role of hydrocortisone
M Toyama and RL Reis
The effects of hydrocortisone on left ventricular force-velocity relations,
systolic length-tension curves, and diastolic pressure- volume curves
(compliance) were determined before and 30 and 60 minutes after a 1 hour
period of normothermic ischemic cardioplegia. Five dogs were given no
hydrocortisone, 5 dogs 150 mg. per kilogram of hydrocortisone immediately
after aortic unclamping, and 5 dogs 150 mg. per kilogram of hydrocortisone
20 minutes before clamping. Thirty minutes after unclamping, there was a 45
per cent decrease in contractility (p less than 0.005). At 60 minutes,
there was a significant improvement (p less than 0.025), although a 32 per
cent depression persisted. There were no differences among the three groups
(p less than 0.05). Dogs not given hydrocortisone before clamping,
compliance decreased 18 per cent (p less than 0.05), and in those given
hydrocortisone immediately after unclamping, compliance decreased 28 per
cent (p less than 0.025). The decreases in compliance in the
hydrocortisone-treated dogs were significantly less (p less than 0.05) than
the decreases observed in the dogs not given hydrocortisone.
