Novel mesh-derived right ventricular free wall longitudinal strain analysis by intraoperative three-dimensional transoesophageal speckle-tracking echocardiography: a comparison with conventional parameters

Longitudinal right ventricular (RV) function is substantial and might be reflected by free wall longitudinal strain (FWLS). Software solutions for FWLS analysis by two-dimensional (2D) and three-dimensional (3D) transesophageal echocardiography (TEE) are available, but data on validation are sparse. In this study, a novel method for FWLS analysis on 3D meshes ("mesh surface", MS-FWLS,) was tested for feasibility and compared to available parameters. 80 patients undergoing left-sided cardiac valve surgery with intraoperative TEE were included retrospectively. 2D-FWLS, 3D-derived (3Dd)-FWLS (assessed in optimized four-chamber views after volume analysis) and MS-FWLS were measured and compared to conventional parameters (3Dd-TAPSE, FAC and RVEF). The mean FWLS values did not differ significantly between methods (- 19.0 +/- 6.1%, - 20.0 +/- 7.3%, - 19.5 +/- 7.3% for 2D-, 3Dd- and MS-FWLS, respectively). No significant differences in the mean FWLS between patients with normal or increased pulmonary artery pressures as well as normal or reduced left ventricular ejection fraction were observed. Agreement was best between 3Dd- and MS-FWLS (r = 0.89, bias = - 1.0%, LOA +/- 6.9%). Conventional echocardiographic parameters yielded poorer intermodality agreement. In patients with discrepant results between 2D- and 3Dd-FWLS, 3Dd-FWLS and MS-FWLS yielded similar results (r = 0.82, bias = - 0.3%, LOA +/- 8.6%), while 2D-FWLS and MS-FWLS did not. Intra- and interobserver variabilities of strain analyses were low. MS-FWLS might represent a promising method to overcome artefacts associated with 2D analysis. Its prognostic relevance needs to be investigated in prospective studies.