Evaluation of the Simpson’s Method to Determine Left Ventricular Ejection Fraction Using the Transgastric Two-Chamber View

INTRODUCTION: Left ventricular chamber size and functional assessment by transesophageal echocardiography can be difficult if visualization is poor in the mid-esophageal views. However, the accuracy of using the Simpson's method in the transgastric 2-chamber (TG2C) as an alternative approach has not been assessed. METHODS: The Simpson's method was performed by 2 independent reviewers using midesophageal 2-chamber (ME2C) and TG2C views. Echocardiographic images were retrieved retrospectively for 49 adult cardiac surgical patients. RESULTS: Two-way random effects intraclass correlation coefficients demonstrated no significant interobserver variability. Linear mixed effects models showed no significant differences in ME2C and TG2C measurements with regard to EDV (P=.4407), ESV (P=.5113), or EF (P=.0610).Compared to the ME2C view, the TG2C view had better image quality of the LV walls (image quality score median interquartile range: 2.00 .00 vs 1.00 1.00; P<.0001), but worse image quality of the mitral annulus (1.00 1.00 vs 2.00 .00; P<.0001) and LV apex (.00 1.00 vs 2.00 1.00; P<.0001). CONCLUSIONS: This study suggests the Simpson's method can be applied to the TG2C view as an alternative to the standard midesophageal method to estimate chamber volumes and EF.