Automated continuous intracoronary thermodilution closely correlated with conventional measurements for microvascular resistance reserve (r=0.89) and significantly reduced procedural time (p=0.013).
Does an automated continuous intracoronary thermodilution method accurately measure absolute coronary flow and microvascular resistance compared to the conventional manual method?
An automated method for continuous intracoronary thermodilution accurately measures microvascular resistance reserve while significantly reducing procedural time compared to the conventional manual approach.
Effect estimate: r = 0.89
p-value: p=0.013
Abstract Aim Microvascular resistance reserve (MRR) as derived from continuous intracoronary thermodilution specifically quantifies microvasculature function. As originally described, the technique necessitates reinstrumentation of the artery and manual reprogramming of the infusion pump when performing resting and hyperemic measurements. To simplify and to render this procedure operator‐independent, we developed a fully automated method. The aim of the present study is to validate the automated procedure against the originally described one. Methods and Results For the automated procedure, an infusion pump was preprogrammed to allow paired resting‐hyperemic thermodilution assessment without interruption. To validate the accuracy of this new approach, 20 automated measurements were compared to those obtained in the same vessels with conventional paired resting‐hyperemic thermodilution measurements (i.e., with a sensor pullback at each infusion rate and manual reprogramming of the infusion pump). A close correlation between the conventional and the automated measuring technique was found for resting flow (Q rest : r = 0.89, mean bias = 2.52; SD = 15.47), hyperemic flow (Q hyper : r = 0.88, mean bias = −2.65; SD = 27.96), resting microvascular resistance (R μ ‐ rest : r = 0.90, mean bias = 52.14; SD = 228.29), hyperemic microvascular resistance R μ ‐ hyper : r = 0.92, mean bias = 12.95; SD = 57.80), and MRR (MRR: r = 0.89, mean bias = 0.04, SD = 0.59). Procedural time was significantly shorter with the automated method (5′25″ ± 1′23″ vs. 4′36″ ± 0′33″, p = 0.013). Conclusion Continuous intracoronary thermodilution‐derived measurements of absolute flow, absolute resistance, and MRR can be fully automated. This further shortens and simplifies the procedure when performing paired resting‐hyperemic measurements.
Candreva et al. (Mon,) conducted a other in Coronary microvascular dysfunction (n=20). Automated continuous intracoronary thermodilution vs. Conventional manual continuous intracoronary thermodilution was evaluated on Microvascular resistance reserve (MRR) correlation and procedural time (r = 0.89, p=0.013). Automated continuous intracoronary thermodilution closely correlated with conventional measurements for microvascular resistance reserve (r=0.89) and significantly reduced procedural time (p=0.013).