Hemodynamic forces assessment in severe aortic stenosis undergoing transcatheter aortic valve intervention

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Abstract Background Estimated hemodynamic forces (HDFs) are a novel and validated marker of cardiac function evaluation computed by standard echocardiography. They have been demonstrated to be altered in many cardiac diseases, such as heart failure. However, their application in valvular disease is still not completely known. Aim to analyze left ventricular (LV) HDFs in patients with severe aortic stenosis before and immediately after transcatheter aortic valve implantation to reveal whether cardiac changes occur early after the procedure. Methods All the patients with severe aortic stenosis referred to ourutively enrolled. Transthoracic echocardiography (TTE) was performed before and early after the procedure (within five days). Standard TTE parameters for volume dimension and function were collected along with peak and mean aortic gradients and aortic valve area. TTE cine loops in 3-2 and 4 chambers were analyzed offline with a dedicated speckle tracking echocardiography (STE) software to compute global longitudinal strain (GLS) and HDFs using LV endocardial displacement and the estimated mitral and aortic valve areas as input. HDFs were computed during the entire cardiac cycle, in systole and diastole, in their two main directions: apex-to-base (AB) and lateral-septal (LS). The LS over AB ratio was also calculated, representing HDFs’ distribution into the LV. HDFs were normalized with LV volumes and expressed as a percentage of the force of gravity. Results 31 patients undergoing TAVI were enrolled (mean age 82 years ± 7, 45 % females, Euroscore II 4.2% ± 2.1, 71% history of CAD). Baseline standard and advanced TTE parameters are described in the table. After the procedure, no significant changes in ejection fraction (55±9 vs. 57±10, p=0.105) were observed, while a trend in GLS improvement was observed even without statistical significance (-16.6±9.1 vs -19.1±5.8, p=0.63). HDFs in the entire cycle showed a significant improvement in terms of magnitude, apical-base (p=0.08) and lateral septal (p=0.01), but no significant changes in the LS/AB ratio were observed, even if there was a slight reduction (p=0.670). A slight improvement in HDFs AB and LS and a reduction in LS/AB ratios were observed in both systole and diastole, even if they were not statistically significant (Table). Conclusions Preliminary data suggest that HDFs by TTE, representing advanced LV function evaluation, showed a trend in improvement after acute pressure unloading in TAVI patients. A greater cohort is needed to expand these data. Figure 1 Table 1