PhD Scientific Days 2023

Clinical Medicine I.

Myocardial Work as an Independent Predictor of Postoperative NT-proBNP after Transcatether Aortic Valve Replacement

Text of the abstract

The treatment of aortic valve stenosis (AS) has been revolutionized by transcatether aortic valve replacement (TAVR). Left ventricular (LV) function is a key element of preprocedural patient assessment, however, conventional echocardiographic parameters are influenced by the increased afterload associated with AS. Global myocardial work index (GWI) is a novel echocardiographic parameter that quantifies myocardial deformation in the context of LV pressure, thus, it may be a reliable measure of LV contractility even with increased afterload.
We aimed to evaluate the LV function of TAVR patients using conventional echocardiographic parameters and GWI, and examine their association with the clinical characteristics of the patients.
84 TAVR candidates were enrolled (age 79±6 years; 48% female). Conventional and advanced echocardiographic measurements were performed prior to TAVR and at a 12-months follow-up visit. We measured ejection fraction (EF), then global longitudinal strain (GLS) by speckle-tracking echocardiography and using LV volume curves estimated from systolic blood pressure and mean transaortic gradient, we quantified GWI. Detailed medical history, symptomatic status and as a marker of congestion, NT-proBNP levels were obtained.
EF did not change (53±13 vs. 55±10 %; p=0.172), while the absolute value of GLS increased substantially (-13.5±4.5 vs. -15.3±3.6 %; p<0.001). GWI decreased significantly (1914±787 vs. 1666±594 mmHg%; p=0.001). TAVR significantly reduced the NT-proBNP levels of the cohort (1057 [586-3037] vs. 627 pg/mL [376-1198]; p<0.001). Using multivariate regression analysis, examining relevant preprocedural clinical and echocardiographic parameters, the presence of atrial fibrillation (AF) (β=0.31; p<0.01), and the preprocedural GWI value (β=-0.32; p<0.01) proved to be significant independent predictors of postprocedural NT-proBNP (R2=0.30; p<0.001).
In our study population GLS and GWI significantly after TAVR. The preprocedural GWI value and the presence of AF proved to be independent predictors of postprocedural NT-proBNP. Accordingly, GWI may help in the improvement of patient selection and the estimation of the clinical prognosis in this population.
The research was supported by the ÚNKP-22-3-I-SE-52 New National Excellence Program of the Ministry for Innovation and Technology from the National Research, Development, and Innovation Fund.