Prognostic value of cardiac ¹²³I‐metaiodobenzylguanidine imaging for predicting cardiac events after transcatheter aortic valve replacement

Abstract

Aims In patients with aortic valve stenosis (AS), cardiac sympathetic nervous (CSN) dysfunction and its improvement after transcatheter aortic valve replacement (TAVR) have been reported. The prognostic impact of CSN function remains unclear. This study investigated the prognostic value of cardiac 123 I-metaiodobenzylguanidine (MIBG) imaging for predicting cardiac events after TAVR. Methods and results This single-centre prospective observational study enrolled patients with AS between July 2017 and May 2019. MIBG scintigraphy was performed before and soon after TAVR to evaluate the late heart-mediastinum ratio (L-H/M). Patients were classified into three pairs of groups based on the baseline and post-TAVR L-H/M (≥2.0 or <2.0) and on the presence of TAVR-related improvement in L-H/M. The study endpoint was the occurrence of major adverse cardiac events (MACE), defined as a composite of all-cause death, non-fatal myocardial infarction, and hospitalization due to heart failure. Among the 187 consecutive patients who underwent TAVR, 107 (27 men; median age: 86 years) were evaluated. Over a median follow-up of 366 days, 15 (14.0%) patients had MACE.

Serial changes in cardiac sympathetic nervous function after transcatheter aortic valve replacement: A prospective observational study using 123I-meta-iodobenzylguanidine imaging

“…Furthermore, there is an increased need for the appropriate selection of patients who would most bene t from TAVR. In our previous study, we demonstrated that CSNF assessment with MIBG imaging could provide essential information about patients' prognosis after TAVR and that patients exhibiting early improvement in late H/M after TAVR had a signi cantly lower incidence of cardiac events than those without such improvement [15]. The present results indicate that late H/M displayed a clearer trend towards improvement at 6-12 months than immediately after TAVR.…”

“…Second, the prognostic bene t from the improvement in CSNF at 6-12 months after TAVR remains unclear because the patients' prognostic information was not included in the present study. However, because the association of early TAVR-related improvement in the late H/M with better prognosis has previously been con rmed [15], the increase in the late H/M revealed in this study should also represent good clinical outcomes after TAVR. Third, there may be some selection bias in sampling, as baseline MIBG imaging could not be performed for critically ill patients with unstable general conditions.…”

“…Moreover, patients with "very severe AS," de ned as mPG ≥60 mmHg and/or Vmax ≥5 m/s, are considered at high risk, and current Japanese guidelines recommend early surgery, even when these patients are asymptomatic [14]. In our present study, patients with a very high mPG (≥58 mmHg) exhibited a higher degree of improvement in CSNF after TAVR, suggesting that patients with a very high baseline mPG would gain the greatest prognostic bene t from TAVR, considering the association of TAVR-related improvement in the late H/M with post-TAVR prognosis [15].…”

Impaired Cardiac Sympathetic Innervation Increases the Risk of Cardiac Events in Heart Failure Patients with Left Ventricular Hypertrophy and Mechanical Dyssynchrony

“…This study did not include any patients who had major valvular heat diseases responsible for advanced heart failure such as aortic stenosis (AS) or mitral regurgitation (MR), who may had been indicated for transcatheter aortic valve implantation (TAVI) or Mitra Clip ® treatment. Because of the possibilities of cardiac MIBG imaging for identifying the therapeutic effects of TAVI or Mitra Clip ® [ 26 , 27 ], a future study will clarify the therapeutic effects on cardiac sympathetic innervation and function in correlation with long-term clinical outcomes. Despite the possible prognostic values of right heart information in left-sided heart failure [ 28 , 29 ], there was no right-heart data available in all patients of this study.…”

Understanding changes in central nervous system function after transcatheter aortic valve replacement

“…In a previous study by the same group, 108 AS patients were evaluated with MIBG imaging before and soon after TAVR and followed to evaluate the occurrence of major adverse cardiac events (MACE), defined as a composite of all-cause death, non-fatal myocardial infarction, and HF hospitalization. 19 After adjustment for possible confounders, the improvement of late H/M was significantly associated with MACE at a median 1year follow-up (adjusted HR: 0.233; 95% CI 0.064-0.856), suggesting some usefulness for prognostic stratification in patients candidates for TAVR. Conversely, in the present study focused on mid-term changes of MIBG imaging, the authors did not provide outcome information nor investigate the prognostic implication of CNS re-assessment following TAVR, which prevents a comprehensive appraisal of the clinical perspectives of these results.…”