Yoshito Kadoya1, Kan Zen2, Nagara Tamaki3, Nobuyasu Ito1, Kensuke Kuwabara1, Michiyo Yamano1, Tetsuhiro Yamano1, Takeshi Nakamura1, Shigenori Matsushima3, Katsuhiko Oka4, Satoshi Numata4, Hitoshi Yaku4, Satoaki Matoba1. 1. Department of Cardiovascular Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto, 602-8566, Japan. 2. Department of Cardiovascular Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto, 602-8566, Japan. k-zen@koto.kpu-m.ac.jp. 3. Department of Radiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan. 4. Department of Cardiovascular Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan.
Abstract
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 123I-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 cm2 vs. 1.6 cm2), 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 < 0.001). On MIBG imaging, delayed H/M significantly increased (2.57 vs. 2.68, p < 0.001), whereas WR decreased (32.2% vs. 26.8%, p < 0.001). In multivariate analysis, higher baseline WR was associated with improvement in WR (> 3%). Female sex, Clinical Frailty Scale score ≤ 5, baseline estimated glomerular filtration rate, and baseline AVA were predictors of improvement in delayed H/M (> 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.
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 123I-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 cm2 vs. 1.6 cm2), 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 < 0.001). On MIBG imaging, delayed H/M significantly increased (2.57 vs. 2.68, p < 0.001), whereas WR decreased (32.2% vs. 26.8%, p < 0.001). In multivariate analysis, higher baseline WR was associated with improvement in WR (> 3%). Female sex, Clinical Frailty Scale score ≤ 5, baseline estimated glomerular filtration rate, and baseline AVA were predictors of improvement in delayed H/M (> 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.