Mid‐esophageal bicaval versus short‐axis view of interatrial septum in two‐dimensional transesophageal echocardiography for diagnosis and measurement of atrial septal pouches

Background Recent studies suggest that the left‐sided septal pouch ( SP ) may increase the risk of cryptogenic stroke and act as an arrhythmogenic substrate. The aim of this study was to compare two transesophageal echocardiography ( TEE ) projections of the interventricular septum: mid‐esophageal bicaval and short‐axis views toward evaluating their ability to detect SP s. Materials and methods A total of 146 patients with both bicaval and short‐axis TEE views were included in this study. The presence of SP s was determined, and they were evaluated for morphology. Results Irrespective of TEE projection view, the left SP was detected in 74 cases (50.7%), right SP in 16 cases (11.0%), and double in one case (0.7%). Agreement between both projections occurred in 119 cases (81.5%) with a weighted kappa coefficient of 0.68 (good agreement). We detected more left SP s from the bicaval view compared to the short‐axis view; however, the observed difference was statistically insignificant (72 vs 59, P  =   .13). The detection of right SP s was higher in the short‐axis view, but also statistically insignificant (9 vs 13, P  =   .38). Bland–Altman analysis revealed a significant difference in the left SP depth with higher values in the bicaval than short‐axis view (systematic difference = 1.17 mm, LoA: −4.88–7.22 mm, P  =   .02, ICC  = 0.58). Conclusions The mid‐esophageal bicaval view should be preferable over mid‐esophageal short‐axis view of interatrial septum for the diagnosis and measurement of the left SP .