What happens to myocardial work after transcatheter aortic valve replacement?

Abstract Background Novel echocardiographic speckle-tracking techniques such as global longitudinal strain (GLS) and myocardial work (MW) have been used in many cardiac conditions for myocardial functional assessment. In severe aortic stenosis (SAS) this evaluation is more challenging since left ventricular (LV) systolic pressure (SP) does not equal non-invasive systolic pressure (NISP) owing to the fixed obstruction of a stenotic valve. Few studies have evaluated the immediate impact of transcatheter aortic valve replacement (TAVR) in patients with SAS on GLS and MW parameters. Aim To assess differences in GLS and MW parameters values, pre- and post-TAVR, in patients with SAS. Methods One-single center retrospective analysis of consecutive patients with SAS submitted to TAVR, between January 2018 and December 2021, who performed transthoracic echocardiography (TTE) bfore and after the procedure (within the same hospital admission). NISP was determined at TTE performance. For pre-TAVR assessment, corrected SP by adding the mean aortic gradient was introduced in the software for MW parameters calculations, namely global work index (GWI), global constructive work (GCW), global wasted work (GWW) and global work efficiency (GWE). Continuous variables were assessed for normality using Shapiro-Wilk test. Normal variables were represented as mean and standard deviation (SD) and compared using a paired-sample t-test. Non-normal variables were represented as median and interquartile range (IQR) and compared using a Wilcoxon-Signed rank test. Statistical significance was defined as two-sided p value < 0.05. All statistical analysis were done with JASP (version 0.16.0.0). Results 50 patients entered the primary analysis. Mean age was 82 years and 56% were female sex. Before TAVR, mean aortic gradient was 49 ± 15 mmHg, mean aortic valve area was 0.76 ± 0.22 cm2 and LV ejection fraction was 52 ± 11%. Table 1 represents the mean GLS and MW parameters values pre- and post-TAVR from our study population. Patients had significant lower values of GWI (1764.4 ± 704.9 vs. 1197 ± 372.6, p < 0.001) and GCW (2309.5 ± 810.9 vs. 1627.8 ± 488.5, p < 0.001) post-TAVR when compared with the pre-TAVR values. There were no significant differences in GLS (p=0.837), GWW (p=0.055) and GWE (P=0.438) values pre- and post-TAVR. Conclusion In our study population, GLS was impaired in patients with SAS and it remained identical after TAVR, suggesting un underlying myopathy that does not reverse immediately after the procedure. Furthermore, MW as assessed by GWI was significantly reduced after TAVR, which may reflect the reduced workload needed after the procedure due to acute afterload reduction. Further studies with longer follow-up are needed to acess the long term impact of TAVR in MW. TAVR MW