Continuous infusion thermodilution for assessment of coronary flow: Theoretical background and in vitro validation

Research output: Contribution to journalArticleAcademicpeer-review

22 Citations (Scopus)
1 Downloads (Pure)

Abstract

Direct volumetric assessment of coronary flow during cardiac catheterization has not been available so far. In the current study continuous infusion thermodilution, a method based on continuous infusion of saline into a selective coronary artery is evaluated. Theoretically, volumetric flow can be calculated from the known infusion rate (Qi), the temperatures of the blood (Tb), the saline (Ti), and the mixture downstream to the infusion site (T). We aimed to validate and optimize the measurement method in an in vitro model of the coronary circulation. Full mixing of infusate and blood was found to be the main prerequisite for accurate determination of the coronary flow. To achieve full mixing the influence of catheter design, infusion rate, and location of temperature measurement were assessed. We found that continuous infusion thermodilution slightly overestimated coronary flow determined by directly measured reference flow by 7 ± 8%, over the entire physiological flow range of 50-250 ml/min. These results were found using a specially designed infusion catheter (infusion mainly through distally located sideholes), a high enough infusion rate (25 ml/min), and measurement of the mixing temperature between 5 and 8 cm distal from the tip of the infusion catheter. Absolute coronary flow rate can be measured reliably by the continuous infusion method when full mixing is present, under the conditions mentioned above. © 2009 IPEM.
Original languageEnglish
Pages (from-to)688-694
JournalMedical Engineering & Physics
Volume31
Issue number6
DOIs
Publication statusPublished - 2009

Fingerprint Dive into the research topics of 'Continuous infusion thermodilution for assessment of coronary flow: Theoretical background and in vitro validation'. Together they form a unique fingerprint.

Cite this