Myocardial strain characteristics and outcomes after transcatheter aortic valve replacement

Abstract

Background: Objective of this study was to make an assessment of standard functional and deformation parameters (strain) in patients after transcatheter aortic valve replacement (TAVR) by cardiac magnetic resonance imaging (CMR) and the evaluation of their prognostic impact. Methods: Patients undergoing TAVR received CMR on a 1.5 T whole-body scanner at 3 months after the procedure. Deformation parameters (strain, strain rate, velocity, displacement) were assessed in longitudinal, circumferential and radial orientation using a feature tracking approach. Primary outcome measure was defined according to Valve Academic Research Consortium-2 (VARC-2) criteria. Results: Eighty-three patients formed the study population. Deformation parameters were significantly reduced in all three orientations for strain (longitudinal: -12.1 ± 5.4% vs. -15.9 ± 1.96%, p < 0.0001; radial: 34.4 ± 15.3% vs. 47.2 ± 11.4%, p < 0.0001; circumferential: -16.8 ± 4.3% vs. -21.1 ± 2.5%, p < 0.0001) and strain rate (longitudinal: -0.79 ± 0.33%/s vs. -0.91 ± 0.23%/s, p = 0.043; radial: 2.5 ± 1.2%/s vs. 2.9 ± 0.9%, p = 0.067; circumferential: -1.1 ± 0.6%/s vs. -1.3 ± 0.3%/s, p = 0.006) in comparison to a healthy control population. Median follow-up was 614 days. During this period, 13 endpoints occurred (cumulative event rate of 10.7%). Patients with event by trend exhibited poorer strain and strain rate in longitudinal and radial orientation without reaching statistical significance (longitudinal strain: -11.2 ± 5.4% vs. -12.3 ± 5.4%, p = 0.52; longitudinal strain rate: -0.73 ± ± 0.23%/s vs. 0.80 ± 0.35%/s, p = 0.53; radial strain: 29.5 ± 19.6% vs. 35.2 ± 14.5%, p = 0.24; radial strain rate: 2.2 ± 1.6%/s vs. 2.6 ± 1.2%/s, p = 0.31). Conclusions: Assessment of left ventricular deformation parameters by CMR revealed functional abnormalities in comparison to healthy controls. Prognostic significance remains to be further investigated.