Cross-sectional multiplane transesophageal echocardiographic measurements: comparison with standard transthoracic values obtained in the same setting.

BACKGROUND: Several algorithms developed for cost-effective use of transesophageal echocardiography (TEE) propose elimination of "screening" transthoracic echocardiographic (TTE) studies. Cross-sectional measurements obtained by TTE (left atrial diameter [LAD], left ventricular internal dimensions in diastole and systole [LVIDd, LVIDs], septal and posterior wall thickness in diastole [VSTd, PWTd], LV end-diastolic and end-systolic volumes [LVEDV and LVESV], and LV ejection fraction [LVEF]) have not been standardized for TEE.
METHODS: Forty-six patients (age 27 to 85 years, 60 +/- 13 years, 25 [54%] women) underwent TEE and TTE studies. TTE was performed while the TEE probe was in place and the patient was still sedated. Standard TTE measurements were compared with corresponding TEE values obtained from mid-esophageal and transgastric views.
RESULTS: Standard TTE measurements compared favorably with those obtained by TEE at the mid-esophageal three-chamber view for LAD (3.9 +/- 0.6 cm vs 4.0 +/- 0.7 cm, P = NS) and at the transgastric long-axis view for LVIDd (4.6 +/- 0.8 cm vs 4.7 +/- 0.8 cm, P = NS), LVIDs (3.1 +/- 0.9 cm vs 3.1 +/- 0.9 cm, P = NS), and VSTd (0.95 +/- 0.18 cm vs 0.98 +/- 0.19 cm, P = NS). Biplane TTE and TEE measurements of LVEDV (106 +/- 35 ml vs 112 +/- 38 ml, P = NS), LVESV (37 +/- 23 ml vs 37 +/- 25 ml, P = NS), and LVEF (67 +/- 14% vs 69 +/- 14%, P = NS) also correlated closely. The negative predictive values of TEE measurements for excluding abnormal LAD, LVIDd, VSTd, PWTd, and LVEF as defined by TTE were 83%, 94%, 95%, 97%, and 97%, respectively.
CONCLUSION: Cross-sectional TEE measurements as obtained in this study are equivalent to standard TTE dimensions and provide reliable information that may facilitate interpretation of TEE studies in the absence of TTE information.