Evolution of non-invasive myocardial work variables after transcatheter aortic valve implantation in patients with severe aortic stenosis.

INTRODUCTION

Guidelines recommend aortic valve replacement in patients with severe aortic stenosis who present with symptoms or left ventricular ejection fraction<50%, both conditions representing a late stage of the disease. Whereas global longitudinal strain is load dependent, but interesting for assessing prognosis, myocardial work has emerged.

AIM

To evaluate acute changes in myocardial work occurring in patients undergoing transcatheter aortic valve implantation (TAVI).

METHODS

Patients who underwent TAVI were evaluated before and after by echocardiography. Complete echocardiographies were considered. Myocardial work indices (global work index, global constructive work, global work efficiency, global wasted work) were calculated integrating mean transaortic pressure gradient and brachial cuff systolic pressure.

RESULTS

One hundred and twenty-five patients underwent successful TAVI, with a significant decrease in mean transaortic gradient (from 52.5±16.1 to 12.2±5.0; P<0.0001). There was no significant change in left ventricular ejection fraction after TAVI. Myocardial work data after TAVI showed a significant reduction in global work index (1389±537 vs. 2014±714; P<0.0001), global constructive work (1693±543 vs. 2379±761; P<0.0001) and global work efficiency (85.0±7.06 vs. 87.1±5.98; P=0.0034). The decrease in global work index and global constructive work after TAVI was homogeneous among different subgroups, based on global longitudinal strain, left ventricular ejection fraction and New York Heart Association status before TAVI. We observed a significant association between global work index and global constructive work before TAVI, and global longitudinal strain degradation after TAVI.

CONCLUSIONS

Myocardial work variables show promising potential in best understanding the left ventricular myocardial consequences of aortic stenosis and its correction. Given their ability to discriminate between New York Heart Association status and global longitudinal strain evolution, we can hypothesize about their clinical value.