Effects of hypoxia, acidosis and peripheral vascular resistance on endocardial viability ratio

In view of the increasing frequency in which cardiac output is pharmacologically altered, the endocardial viability ratio was evaluated experimentally in the dog as an additional means by which cardiac function might be monitored. The endocardial viability ratio provided useful information for cardiac function in situations of decreased peripheral resistance. The limitations of the endocardial viability ratio were evident in conditions of acidosis, hypoxia and increased peripheral resistance. Additional work is indicated prior to firmly establishing the endocardial viability ratio as a useful clinical monitor.