Three-Dimensional Echocardiographic Approach to Mitral Valve After Transcatheter Edge-to-Edge Repair

BACKGROUND: Evaluation of the mitral valve during transcatheter edge-to-edge repair (TEER) for management of mitral regurgitation is commonly guided by intraprocedural interventional transesophageal echocardiography (TEE). The risk of iatrogenic mitral stenosis (MS) remains a concern, particularly in patients requiring multiple clips, since the mitral valve orifice area (MVA) is reduced. The value of conventional flow-based echocardiographic methods to rule out MS is limited by intraprocedural and general anesthesia (GA)-induced hemodynamic variability. This retrospective study introduces the novel adaptation of a 3-dimensional (3D) Orifice Area (3DOA) technique to evaluate post-TEER MVA. We evaluated the degree of agreement between MVAs derived via TEE 3DOA, TEE pressure half-time (PHT), and postprocedure transthoracic echocardiography (TTE) PHT with patients awake. METHODS: TEE and TTE images from 20 adult patients with severe mitral regurgitation undergoing a TEER (MitraClip, Abbott) procedure were retrospectively reviewed. MVAs obtained by MTEE 3DOA and TEE PHT under GA were compared to those acquired with TTE PHT with patients awake. Agreement was assessed via calculation of Bland-Altman 95% limits of agreement and Lin's concordance correlation coefficients, both with 95% confidence intervals (CIs). RESULTS: There was good agreement between TEE 3DOA-derived MVA measurements under GA and TTE PHT-derived MVA measurements in awake patients, as reflected by Bland-Altman (lower limit of agreement: -.0.45 [95% CI, -.58 to -.31] and upper limit of agreement: 0.26 [95% CI, 0.12-0.4]), and an excellent concordance correlation coefficient value (0.95 [95% CI, 0.86-0.98]). In contrast, agreement between TEE PHT-derived MVA and TTE PHT-derived MVA was weak, with much broader limits of agreement (lower limit of agreement: -1.6 [95% CI, -2.19 to -1.02] and upper limit of agreement: 1.43 [95% CI, 0.84-2.01]) and a weak concordance correlation coefficient value (0.46 [95% CI, 0.02-0.75]). CONCLUSIONS: In this retrospective cohort study, we demonstrated excellent agreement between TEE-3DOA-derived MVA under GA and TTE PHT-derived MVA in awake patients, but not between TEE versus TTE PHT. These findings warrant further validation in larger patient datasets to assess the utility of 3D echocardiographic approaches in evaluating MVA after TEER.