A new carbon based oxygen sensor for race adaptive cardiac pacing has
been developed. It measures oxygen partial pressure In mixed venous bl
ood. The system was implanted in six sheep with a mean follow-up time
of 261 days after implant. The sensor reacted in a physiological manne
r when the animals were at rest as well as during exercise. Long-term
sensor stability and sensitivity were satisfactory, and we found excel
lent correlation with spontaneous heart rate variations and with oxyge
n saturation measurements. The sensor shows great promise although our
experience is still limited and further development on the concept is
on-going.