Computed tomography derived predictors of left ventricular obstruction after TAVR

Background: Left ventricular obstruction (LVO) is an infrequent complication following transcatheter aortic valve replacement (TAVR) that can lead to severe hemodynamic decompensation. Previous studies have analyzed the pathophysiology of this clinical entity; however, little is known about the anatomical characteristics as assessed by computational tomography (CT) of patients at risk.

Methods: Data from 349 patients were retrospectively analyzed from a single center registry of patients undergoing TAVR at San Raffaele Hospital, Milan, Italy, between January 2020 and December 2021. All patients with aortic valve stenosis and available pre-procedural CT data were included. Patients with previous heart valve surgery/interventions were excluded.

Results: Post-procedurally, a total of 57 patients (16.3 %) developed LVO. They were more frequently older (83.2 vs 81.4, p = 0.04), females (67 % vs. 47 %, p < 0.05) and had smaller body surface areas and weight. CT analysis between the two groups demonstrated an acuter aorto-mitral angle (107 vs 114°, p < 0.001), shorter interventricular septum to leaflet coaptation distance (SLCL, 22.1 vs 28.1 mm, p < 0.001), smaller telo-systolic left ventricular areas (267 vs 714 mm2) and smaller LVOT area (404 vs 470 mm2, p < 0.001) in patients with LVO. Multivariate regression analysis identified as parameters able to predict the occurrence of LVO the telo-systolic LV area (OR, 0.998; 95 % CI 0.996-0.999; p = 0.001) and the anatomical distance between the interventricular septum and the point of leaflet coaptation (OR, 0.92; 95 % CI 0.86-0.99; p = 0.02).

Comclusion: This is the first study identifying pre-procedural CT imaging predictors of patients at risk for LVO following TAVR. Further multicenter studies with systematic follow up will be needed to confirm these findings.