Association of Cardiac Damage and Computed Tomography–Derived Extracellular Volume in Patients Undergoing Transcatheter Aortic Valve Implantation

Background: Extravalvular cardiac damage (EVCD) and extracellular vol- ume (ECV) are key determinants of poor outcomes in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI). We aimed to assess the association of ECV derived by means of cardiac computed tomography (CT) with EVCD before and after TAVI, its impact on left ventricular reverse remodelling, and functional improve- ments at 3-month follow-up in patients with severe AS undergoing TAVI. Methods: This was a prospective study of 73 consecutive patients undergoing TAVI, with CT-derived ECV assessment and baseline and follow-up echocardiographic evaluation of EVCD. After identifying the best ECV cutoff for predicting EVCD progression and advanced EVCD (stages 3-4) at follow-up according to the Youden index, patients were divided into low (n¼ 39) and high (n¼ 34) ECV groups. Predictors of EVCD progression, advanced EVCD, and functional improvements at follow-up were identi ed by means of logistic regression analysis. Results: At 3-month follow-up, 34.2% of patients showed EVCD pro- gression. ECV 32% accurately predicted EVCD progression and stages 3-4 (area under the receiver operating characteristic curve 0.66, P < 0.001). At follow-up, patients with high ECV were more frequently in stages 3-4 (P¼ 0.011) and had a 50% progression rate (P¼ 0.012). Conversely, patients with low ECV exhibited greater LV reverse remodelling (P¼ 0.004) and improvement in New York Heart Association (NYHA) functional class at both 3-month (P¼ 0.020) and 6-month (P¼ 0.001) follow-ups compared with patients with high ECV. High ECV emerged as an independent predictor of EVCD progression (odds ratio [OR] 4.34, 95% CI 1.36-13.78, P¼ 0.013), stages 3-4 (OR 5.71, 95% CI 1.77-18.42, P¼ 0.004) and lack of improvement in NYHA functional class (OR 3.22, 95% CI 1.14-9.09, P¼ 0.027) at 3- month follow-up. Conclusions: Elevated CT-derived ECV was associated with EVCD pro- gression and reduced functional improvement after TAVI.