Accuracy and reliability of non-invasive cardiac output: the future in cardiology?

A new generation of non-invasive cardiac output monitors provides an alternative to using conventional invasive methods such as thermodilution and direct Fick. The Bioz.com measures changes in thoracic electrical bioimpedance (TEB) of the descending aorta. The Innocor uses the principle of inert gas rebreathing. Simultaneous TEB and thermodilution cardiac output measurements were taken from 27 patients undergoing right heart catheterisation. Linear regression analysis showed good correlation between thermodilution and TEB about the line y = 0.85x + 0.63 (r = 0.91, P<0.0001). Preliminary data from the Innocor suggest comparable accuracy, continuous monitoring, portability, ease of use and low cost for a variety of applications in cardiology.