A temperature-sensitive cardiac pacemaker

Abstract

An artificial cardiac pacemaker which is sensitive to the temperature of blood in the right atrium has been fabricated. For a temperature change of 20°C the circuit achieves 90% of its final response within a period of 18s. In the authors’ opinion this is satisfactory since changes in blood temperature are generally small. Cardiac output in dogs rose from 2.37 ± 0.65 to 4.54 ± 1.15 l/min when the rate was increased from 202-6 beats/min (b.pm.)at 37.6° C to 231.6 b. p.m. at 41°C. Cardiac output was found, from statistical observation, to be improved at temperatures over 39.6°C.