Abstract 14068: Effect of Tricuspid Regurgitation on Thermodilution Cardiac Output Assessment
Background: It is generally accepted that tricuspid regurgitation (TR) affects the reliability of the thermodilution (TD) cardiac output technique in patients with pulmonary artery catheters. Previous studies investigating the effect of TR on thermodilution methods are small, outdated and report conflicting results. The purpose of this study was to determine what effect TR has on TD cardiac output in present day cardiac catheterization labs.
Methods: We examined right heart catheterizations (RHCs) performed at our center from 2013 to 2014. RHC data were only included if an evaluation for TR via echocardiogram had been performed within a 14-day window of the RHC date. The agreement between TD and Fick cardiac output was assessed by Bland and Altman’s limits of agreement by calculating the mean of the differences between the Fick and TD methods ± 2 standard deviations. In addition the intra-class correlation coefficient (ICC) was computed, where <0.4 indicates poor agreement, 0.4-0.75 indicates fair agreement, >0.75 indicates excellent agreement.
Results: A total of 475 RHCs were obtained that met the inclusion criteria; 69 of which had severe TR, 68 moderate TR and 338 with mild or no TR. Echocardiograms were performed on average 3.7 days within the RHC date. The mean difference between TD and Fick cardiac output in the entire population was 0.46 ± 2.62 L/min. In the population with non-severe TR vs severe TR the mean differences were respectively, 0.43 ± 2.64 L/min and 0.65 ± 2.44 L/min. The ICC for the whole population was 0.74 (95% confidence interval, 0.70-0.78). For the non-severe TR vs severe TR, the ICC was 0.76 (0.71-0.80) and 0.58 (0.42-0.72) respectively.
Conclusion: The Bland and Altman analysis showed a greater mean difference between TD and Fick in the setting of severe TR, but the standard deviations were both similarly wide. The ICC analysis suggests that there is excellent agreement in the non-severe TR group but only fair agreement in the severe TR group, though the 95% confidence intervals did barely overlap. To our knowledge this study is the largest study to investigate the effect of TR on TD cardiac output assessment. The small number of severe TR cases may have affected the stability of results and more data may be necessary to improve precision of estimation.
Author Disclosures: B. Koo: None. D. Wang: None. C. Guerrero Miranda: None. A. Negassa: None. J. Tauras: None.
- © 2016 by American Heart Association, Inc.