P1221Effect of transcatheter aortic valve implantation on cardiac sympathetic nervous function assessed by 123I-metaiodobenzylguanidine scintigraphy in patients with severe aortic stenosis

Abstract

Abstract Background Cardiac sympathetic nervous (CSN) function assessed by 123I-metaiodobenzylguanidine (MIBG) scintigraphy is associated with poor prognosis in patients with heart failure. Purpose The aim of this study was to investigate the effects of transcatheter aortic valve implantation (TAVI) on CSN function in patients with severe aortic stenosis (AS) using MIBG scintigraphy. Methods This was a single-center prospective observational study that enrolled patients between July 2017 and July 2018. Among 77 registered patients who scheduled to undergo TAVI, 35 patients (7 men; mean age: 87 years) were evaluated. The MIBG scintigraphy was performed at baseline and 6 months after TAVI procedure to evaluate the heart-mediastinum ratio (H/M) and washout rate (WR). The MIBG parameter changes were compared with B-type natriuretic peptide (BNP) levels and echocardiographic parameters, including aortic valve area (AVA), peak velocity (Vmax), mean pressure gradient (PG), and left ventricular ejection fraction (LVEF). Results All patients successfully underwent TAVI with improved BNP level (388±341 pg/mL vs. 167±118 pg/mL, p<0.001). The AVA, Vmax, mean PG and LVEF improved after TAVI (0.6±0.2 cm2 vs. 1.6±0.5 cm2, p<0.001; 4.6±0.8 m/s vs. 2.1±0.3 m/s, p<0.001; 54±20 mmHg vs. 9±3 mmHg, p<0.001; 58±11% vs. 63±9%, p=0.01, respectively). In the MIBG imaging, the delayed H/M significantly increased (2.5±0.6 vs. 2.6±0.7, p=0.03), and the WR decreased (32±8% vs. 29±8%, p=0.047) after TAVI. There was a correlation between the changes in the MIBG parameters and the change in mean PG from baseline to 6 months (delayed H/M: r=0.391, p=0.02; WR: r=0.347, p=0.04). Multivariate logistic regression analysis showed that baseline mean PG was an independent predictor of improved both delayed H/M and WR (odds ratio=1.062; 95% confidence interval: 1.009–1.137; p=0.042). Conclusions TAVI can improve the CSN function in patients with AS. Such CSN improvement was related with hemodynamic changes. Acknowledgement/Funding None