P404 MYOCARDIAL WORK EVALUATION IN PATIENTS WITH SEVERE AORTIC STENOSIS UNDERGOING TRANSCATHETER AORTIC VALVE REPLACEMENT

Abstract

Abstract Background myocardial work (MW) is a novel echocardiographic technique that enables the study of left ventricular performance. It overcomes speckle tracking echocardiography (STE) limitations, dependent on afterload, which is increased in patients with severe aortic stenosis (AS). Aims: To evaluate myocardial performance indexes obtained with MW in patients with AS and indication to percutaneous aortic valve replacement (TAVR) before and after the procedure. Methods patients with severe AS and preserved left ventricular systolic function (LVEF) and indication to TAVR underwent complete echocardiographic evaluation the day before and within two days after the procedure. MW indices were calculated considering noninvasive systolic blood pressure (SBP) and corrected for the mean transvalvular aortic gradient. Results 39 patients (78±6 years, 61.5% women) were enrolled, they presented at baseline preserved LVEF (59.4±8.2%) and reduced global longitudinal strain (GLS) (–16.8±3.3%). Corrected global work index (cGWI) and corrected global constructive work (cGCW) appeared elevated before the procedure, and were significantly reduced within 2 days after TAVR (cGWI –2460.5±839.7 mmHg% vs 1844.4±521.6 mmHg%, p<0.01; cGCW 3061.3 ± 796.0 vs 2277.4 ± 536.5mmHg%, p<0.01). Adjusted global wasted work (cGWW) and adjusted global work efficiency (cGWE) did not change significantly after TAVR (cGWW 262.6±151.8 vs 244.2±129.2 mmHg%, p=0.236; cGWE 90.1±4.5 vs 88.5±5.2%, p=0.079) in the overall population. In the subgroup of patients who had not developed new atrioventricular or intraventricular conduction abnormalities, cGWW also significantly decreased following TAVR (275±152.6 vs 216.3 ± 99.7 mmHg%, p=0.018), with no change in cGWE (89.7±4.8 vs 89.3±5.8%, p=0.838). Conclusions The reduction in cGWI and cGWC values and thus myocardial oxygen consumption in the immediate post–TAVR is attributable to the reduction in afterload. Left ventricular function abnormalities do not totally regress after the procedure, although the lack of reduction in cGWW could be partly due to the development of atrioventricular or intraventricular conduction defects. Further studies are desirable to define a role of MW in prognostic stratification of patients with severe AS.