Functional and structural reverse myocardial remodeling following transcatheter aortic valve replacement: a prospective cardiovascular magnetic resonance study

Background: Since cardiovascular magnetic resonance (CMR) imaging allows comprehensive quantification of both myocardial function and structure we aimed to assess myocardial remodeling processes in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR). Methods: CMR imaging was performed in 40 patients with severe AS before and 1 year after TAVR. Image analyses comprised assessments of myocardial volumes, CMR-feature-tracking based atrial and ventricular strain, myocardial T1 mapping, extracellular volume fraction-based calculation of left ventricular (LV) cellular and matrix volumes, as well as ischemic and non-ischemic late gadolinium enhancement analyses. Moreover, biomarkers including NT-proBNP as well as functional and clinical status were documented. Results: Myocardial function improved 1 year after TAVR: LV ejection fraction (57.9 +/- 16.9% to 65.4 +/- 14.5%, p= 0.002); LV global longitudinal (- 21.4 +/- 8.0% to -25.0 +/- 6.4%, p < 0.001) and circumferential strain (- 36.9 +/- 14.3% to - 42.6 +/- 11.8%, p = 0.001); left atrial reservoir (13.3 +/- 6.3% to 17.8 +/- 6.7%, p= 0.001), conduit (5.5 +/- 3.2% to 8.4 +/- 4.6%, p= 0.001) and boosterpump strain (8.2 +/- 4.6% to 9.9 +/- 4.2%, p= 0.027). This was paralleled by regression of total myocardial volume (90.3 +/- 21.0 ml/m(2) to 73.5 +/- 17.0 ml/m(2), p <0.001) including cellular (55.2 +/- 13.2 ml/ m(2) to 45.3 +/- 11.1 ml/m(2), p < 0.001) and matrix volumes (20.7 +/- 6.1 ml/m(2) to 18.8 +/- 5.3 ml/m(2), p = 0.036). These changes were paralleled by recovery from heart failure (decrease of NYHA class: p < 0.001; declining NT-proBNP levels: 2456 +/- 3002 ng/L to 988 +/- 1222 ng/L, p = 0.001). Conclusion: CMR imaging enables comprehensive detection of myocardial remodeling in patients undergoing TAVR. Regression of LV matrix volume as a surrogate for reversible diffuse myocardial fibrosis is accompanied by increase of myocardial function and recovery from heart failure. Further data are required to define the value of these parameters as therapeutic targets for optimized management of TAVR patients.

Automated summary

This study aimed to assess myocardial remodeling processes in patients with severe aortic stenosis undergoing transcatheter aortic valve replacement using cardiovascular magnetic resonance imaging. The results showed that 1 year after TAVR, myocardial function improved, myocardial volume regressed, and heart failure recovery occurred.