Blood flow dynamics with four-dimensional flow cardiovascular magnetic resonance in patients with aortic stenosis before and after transcatheter aortic valve replacement

Abstract

Background Pre- and post-procedural hemodynamic changes which could affect adverse outcomes in aortic stenosis (AS) patients who undergo transcatheter aortic valve replacement (TAVR) have not been well investigated. Four-dimensional (4D) flow cardiovascular magnetic resonance (CMR) enables accurate analysis of blood flow dynamics such as flow velocity, flow pattern, wall shear stress (WSS), and energy loss (EL). We sought to examine the changes in blood flow dynamics of patients with severe AS who underwent TAVR. Methods We examined 32 consecutive severe AS patients who underwent TAVR between May 2018 and June 2019 (17 men, 82 ± 5 years, median left ventricular ejection fraction 61%, 6 self-expanding valve), after excluding those without CMR because of a contraindication or inadequate imaging from the analyses. We analyzed blood flow patterns, WSS and EL in the ascending aorta (AAo), and those changes before and after TAVR using 4D flow CMR. Results After TAVR, semi-quantified helical flow in the AAo was significantly decreased (1.4 ± 0.6 vs. 1.9 ± 0.8, P = 0.002), whereas vortical flow and eccentricity showed no significant changes. WSS along the ascending aortic circumference was significantly decreased in the left (P = 0.038) and left anterior (P = 0.033) wall at the basal level, right posterior (P = 0.011) and left (P = 0.010) wall at the middle level, and right (P = 0.012), left posterior (P = 0.019) and left anterior (P = 0.028) wall at the upper level. EL in the AAo was significantly decreased (15.6 [10.8–25.1 vs. 25.8 [18.6–36.2]] mW, P = 0.012). Furthermore, a significant negative correlation was observed between EL and effective orifice area index after TAVR (r = − 0.38, P = 0.034). Conclusions In severe AS patients undergoing TAVR, 4D flow CMR demonstrates that TAVR improves blood flow dynamics, especially when a larger effective orifice area index is obtained.

Comparison of 1-year Follow-up Echocardiographic Outcomes of Sapien 3 Versus Evolut R Bioprosthetic Transcatheter Aortic Valves: A Single-center Retrospective Iranian Cohort Study

“…39,40 The blood flow patterns vary between TAVI, the surgical aortic valve replacement, and the natural valve, which could affect pressure recovery. 41,42 Thus, current data of echo-Doppler gradients in TAVI should be corroborated because of the unique designs of TAVI. Niderberger et al 39 used a pulsatile model to exhibit the degree of pressure recovery.…”

The Impact of Severe Ventricular Remodeling on Quality-of-Life Outcomes after Transcatheter Aortic Valve Replacement

“…Cardiac magnetic resonance (CMR) is apt in this respect, as it provides accurate structural measurements while also revealing tissue properties and even hemodynamic patterns. 16,17 Tissue fibrosis, of note, has been correlated with both symptoms and prognosis in AS. 1 Valvulo-arterial impendence is another measure that may gauge the whole syndrome of AS by intentionally accounting for the interaction among ventricle, valve, and vasculature.…”

Large field-of-view intravascular ultrasound for actual valve-in-valve transcatheter heart valve expansion. A Pilot study.

“…[1][2][3][4][5] A few in vitro studies reported a substantial impact of actual THV frame geometry (eccentricity/non-round shape and under-expansion) on the altered trans-valvular ow characteristics. [6][7][8][9][10] Large eld-of-view intravascular ultrasound (IVUS) offers a unique tomographic perspective for a direct peri-procedural measure of THV stent frame and lea et geometry. [11][12][13][14][15] We compared the peri-procedural IVUS assessment of SAPIEN 3 THV expansion deployed during VIV transcatheter mitral (TMVR) or tricuspid valve replacement (TTVR) versus the post-procedural multislice computed tomography (MSCT) and assessed the correlation between THV dimensions in MSCT and predischarge transvalvular gradients.…”