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

摘要

Purpose The effects of transcatheter aortic valve replacement (TAVR) on cardiac sympathetic nervous (CSN) function have not been fully explored. This study aimed to investigate the early (within 2 weeks) effects of TAVR on CSN function in patients with severe aortic valve stenosis (AS) using I-123-metaiodobenzylguanidine (MIBG) scintigraphy. Methods Of 143 consecutive patients who were scheduled to undergo TAVR, 67 (18 men; median age 86 years) were evaluated in this single-centre prospective observational study. MIBG scintigraphy was performed at baseline and 3-14 days after the TAVR procedure to evaluate the heart-mediastinum ratio (H/M) and washout rate (WR). Differences between baseline and post-TAVR MIBG parameters were analysed. MIBG parameter changes were compared with echocardiographic parameters. Furthermore, factors involved in the improvement in MIBG parameters were investigated. Results All patients successfully underwent TAVR with improved echocardiographic parameters, including aortic valve area (AVA; 0.6 cm(2) vs. 1.6 cm(2)), peak velocity (4.5 m/s vs. 2.0 m/s), mean pressure gradient (50 mmHg vs. 9 mmHg), and left ventricular ejection fraction (56% vs. 62%) (all p 3%). Female sex, Clinical Frailty Scale score 0.1). Baseline AVA and E/E ' were independent predictors of improvement in both WR and delayed H/M. Conclusions The CSN function was impaired in patients with AS, as assessed using MIBG scintigraphy. WR and delayed H/M improved immediately after TAVR. Improvement in CSN function may be related to echocardiographic AS severity at baseline before TAVR.