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Background: Invasive cardiac output (CO) is measured with the thermodilution (TD) or the indirect Fick method (iFM) in right heart catheterization (RHC). The iFM estimates CO using approximation formulas for oxygen consumption ([Formula: see text]O 2 ), but there are significant discrepancies (> 20%) between both methods. Although regularly applied, the formula proposed by Krakau has not been validated. We compared the CO discrepancies between the Krakau formula with the reference (TD) and three established formulas and investigated whether alterations assessed in cardiac magnetic resonance imaging (CMR) determined the extent of the deviations., Methods: This retrospective study included 188 patients aged 63 ± 14 years (30% women) receiving both CMR and RHC. The CO was measured with TD or with the iFM using the formulas by Krakau, LaFarge, Dehmer, and Bergstra for [Formula: see text]O2 estimation (iFM-K/-L/-D/-B). Percentage errors were calculated as twice the standard deviation of the difference between two CO methods divided by their means; a cut-off of < 30% was regarded as acceptable. The iFM and TD-derived CO ratio was built, and deviations > 20% were counted. Logistic regression analyses were performed to identify determinants of a deviation of > 20%., Results: The TD-derived CO (5.5 ± 1.7 L/min) was significantly different from all iFM (K: 4.8 ± 1.6, L: 4.3 ± 1.6; D: 4.8 ± 1.5 L/min; B: 5.4 ± 1.8 L/min all p < 0.05). The iFM-K-CO differed from all methods (p < 0.001) except iFM‑D (p = 0.19). Percentage errors between TD-CO and iFM-K/-L/-D/-B were all beyond the acceptance limit (44/45/44/43%), while percentage errors between iFM‑K and other iFM were all < 16%. None of the parameters measured in CMR was predictive of a discrepancy of > 20% between both methods., Conclusion: The Krakau formula was comparable to other iFM in estimating CO levels, but none showed satisfactory agreement with the TD method. Improved derivation cohorts for [Formula: see text]O 2 estimation are needed that better reflect today's patients undergoing RHC., (© 2023. The Author(s).)

Introduction: Simulation technology has an established role in teaching technical skills to cardiology fellows, but its impact on teaching trainees to interpret coronary angiographic (CA) images has not been systematically studied. The aim of this randomized controlled study was to test whether structured simulation training, in addition to traditional methods would improve CA image interpretation skills in a heterogeneous group of medical trainees., Methods: We prospectively randomized a convenience sample of 105 subjects comprising of medical students (N = 20), residents (N = 68) and fellows (N = 17) from the University of Arizona. Subjects were randomized in a stratified fashion into a simulation training group which received simulation training in addition to didactic teaching (n = 53) and a control training group which received didactic teaching alone (n = 52). The change in pre and post-test score (delta score) was analyzed by a two-way ANOVA for education status and training arm., Results: Subjects improved in their post-test scores with a mean change of 4.6 ± 4.0 points. Subjects in the simulation training arm had a higher delta score compared to control (5.4 ± 4.2 versus 3.8 ± 3.7, p = 0.04), with greatest impact for residents (6.6 ± 4.0 versus 3.5 ± 3.4) with a p = 0.02 for interaction of training arm and education status., Conclusions: Simulation training complements traditional methods to improve CA interpretation skill, with greatest impact on residents. This highlights the importance of incorporating high-fidelity simulation training early in cardiovascular fellowship curricula., (© 2022. The Author(s).)

Background: To prevent complications, uncontrolled movement of the guidewire during a coronary intervention should be avoided. Unintentional withdrawal of the wire can result in the inability to recross a lesion with the risk of myocardial infarction. On the other hand, unintended forward pushing can lead to a coronary perforation. Thus, interventionalists in training should practice keeping the coronary guidewire in a stable position to prevent complications. For this purpose, a skill trainer has been developed, which provides the possibility of unlimited practice outside of the cath lab.The purpose of this study was to assess the effectiveness and the validity of this skills trainer., Methods: Ten novices and 10 participants with experience in diagnostic catheterization underwent training on the skills trainer consisting of 25 procedures. To assess the efficacy of the training module, the mean score of the first 3 procedures was compared with the final 3 procedures in the novice and the advanced group. To determine the construct validity of the simulator, a group of experts (E; performed >1000 percutaneous coronary interventions) also underwent evaluation on the skills trainer. For each procedure, the change in position of the guidewire as well as the time was determined and combined into a skills score with a maximum of 15 points., Results: The novice and the advanced group improved significantly throughout the training on the simulator (N: 7.1 ± 2.6 to 12.2 ± 2.0, P = 0.007; A: 8.3 ± 2.0 to 13.2 ± 1.0, P = 0.005, Wilcoxon).The experts scored significantly higher than novices or the advanced participants during their first 3 procedures (E: 12.9 ± 1.0; N: 7.1 ± 2.6, P = 0.001; A: 8.3 ± 2.0, P = 0.001; Mann-Whitney U )., Conclusions: This low-cost task trainer is a valid and effective tool to train adequate balloon/stent exchange while keeping the guidewire in a stable position. Whether the skills acquired on the task trainer can be transferred to procedures performed on patients needs further investigation., Competing Interests: The authors declare no conflict of interest., (Copyright © 2022 Society for Simulation in Healthcare.)