Myocardial metabolism during prolonged selectived hypothermic coronary perfusion

In the study discussed below, we assessed the myocardial protection provided by our method of selective hypothermic coronary perfusion. Using arterial and coronary venous blood samples, the following biochemical aspects of myocardial metabolism were calculated: 1) coronary arteriovenous (A-V) pH difference, 2) O2 difference, 3) CO2 difference, 4) respiratory quotient, 5) coronary A-V pyruvate difference, 6) lactate difference, 7) cardiac excess lactate, and 8) redox potential difference. Results indicate that, during coronary perfusion performed according to out method, metabolic changes are minimal and easily reversible shortly after coronary perfusion is terminated.

A disposable venting system

A disposable venting system that has been utilized in over 300 cardiac operations is described. The system facilitates reduction of bubble formation in the cardiac chambers and removal of air bubbles with minimal time and effort and maximal safety.

Morphologic alterations in sheep after implantation of the Akutsu total artificial heart

The present report describes morphologic alterations produced in sheep after implantation of a four-chambered total artificial heart. Two groups of sheep were studied. The first group was given no special antishock therapy and had an average survival time of 25.8 hours. Major morphologic changes produced in the first group were focal infarction and massive hemorrhage of the large and small bowel, ascites, severely altered lungs and multiple infarcts in the kidneys. The second group of sheep was given antishock therapy and showed an average survival time of 35.4 hours. Severe morphologic alterations in this group were generally absent in all organs except the lungs, which showed varying degrees of congestion, hemorrhage, edema, pneumonitis and atelectasis. Death in both of the above groups was due to development of irreversible hypotension and respiratory failure.