Left Atrial Strain Quantification by Intraoperative Transesophageal Echocardiography: Validation With Transthoracic Echocardiography.

ABSTRACT

OBJECTIVE: Whereas left atrial (LA) strain has been well-validated using transthoracic echocardiography (TTE), its detection using transesophageal echocardiography (TEE) has not been studied. Conventional transesophageal views are known to be limited due to the posterior location of the LA. Here, the feasibility and accuracy of the deep transgastric long-axis LA focused view for peak atrial longitudinal strain (PALS) quantification was tested. DESIGN: This was a retrospective study of patients who underwent elective cardiac surgery between 2018 and 2020. TEE deep transgastric long-axis view was compared to TTE 4-chamber atrial focused view as the reference standard. LA area, volume, and PALS were quantified independently. SETTING: At Weill Cornell Medicine, a single, large academic medical center. PARTICIPANTS: The population comprised 42 patients undergoing cardiac surgery who had a TTE and TEE within 14.9 ± 20.8 days. INTERVENTIONS: TTE, TEE, and cardiac surgery. MEASUREMENTS AND MAIN RESULTS: TEE-derived PALS strongly correlated with TTE- derived PALS (r = 0.92, p < 0.001), though absolute PALS were lower (20.7 ± 6.0% v 25.7 ± 6.8%; p < 0.001). Mean TEE-derived atrial length was similar to TTE-derived length (5.18 ± 0.61 cm v 5.24 ± 0.61 cm; p = 0.38), but mean LA area was significantly smaller (16.7 ± 3.5 cm2v 18.9 ± 3.7 cm2; p < 0.001), with significant correlations between the 2 modalities for both (r = 0.74, 0.74, respectively; all p < 0.001). CONCLUSION: This exploratory study supported the feasibility of TEE for assessing LA longitudinal strain. There was an excellent correlation between atrial strain derived via TEE versus TTE, although values tended to be smaller on TEE, and bias between values was highly variable, suggesting that the values were not interchangeable.