Variability in Interpretation of Echocardiographic Signs of Tamponade: A Survey of Emergency Physician Sonographers

Abstract

BackgroundCardiac tamponade is associated with high mortality, and making the diagnosis is a core skill of emergency physicians. Proper diagnosis relies on specific clinical and echocardiographic findings. It is not known whether expert sonographers consistently recognize echocardiographic signs of tamponade. ObjectivesTo assess whether expert sonographers agree on echocardiographic signs of tamponade. MethodsA 20-question survey consisting of 18 cine loops and 2 still images was distributed to the Academy of Emergency Ultrasound Section of the Society for Academic Emergency Medicine. Respondents answered “yes” or “no” to whether there was echocardiographic evidence of tamponade. Subgroup analyses of demographics and echocardiographic views were reported. The data were analyzed using Krippendorff's alpha (α) to assess interrater reliability (IRR) between respondents. ResultsEighty-four physicians responded and 56 completed the survey. All partial and completed surveys were analyzed. The overall IRR was poor (α = 0.60, 95% confidence interval [CI] 0.44–0.76). Residency graduation within 5 years (α = 0.66, 95% CI 0.5–0.8) was associated with higher IRR compared with those > 5 years (α = 0.53, 95% CI 0.37–0.69). The highest IRR was observed when images of mitral valve inflow pulse-wave Doppler (α = 0.81, CI 0.70–0.92) were used and the poorest IRR was on images from the parasternal short view (α = 0.28, 95% CI 0.05–0.49). ConclusionThere was poor agreement among expert emergency medicine sonographers in identifying echocardiographic signs of cardiac tamponade from a single cine loop or clip without clinical context. Further investigation is warranted to understand differences in recognition of clinical tamponade.