Eligibility criteria.

Background
Transcatheter Aortic Valve Implantation (TAVI) procedures are rapidly expanding, necessitating a more extensive stratification of patients with aortic stenosis. Especially in the high-risk group, some patients fail to derive optimal or any benefits from TAVI, leading to the risk of futile interventions. Despite consensus among several experts regarding the importance of recognizing and anticipating such interventions, the definition, and predictive criteria for futility in TAVI remain ambiguous.
Aim
The purpose of this study is to explore the literature addressing the definition, predictive criteria, and medical predictive models for futility in cases of TAVI.
Design
A scoping review was conducted by two researchers and reported in accordance with the PRISMA-ScR guidelines.
Eligibility criteria
Studies addressing futility in TAVI, including definitions, predictive variables, and models, were included without restrictions on study design but were excluded study only on surgical valve replacement, valve in valve or aortic stenosis causes by other pathology than calcification.
Information sources
We identified 129 studies from five key sources: CINAHL, PUBMED, the Cochrane Library, ClinicalTrials.gov, and EMBASE. The literature search was conducted in two rounds—first in February 2024 and again in October 2024—using no restrictions on the year of publication or the language of the studies. Additional references were included through cross-referencing.
Results
The definition of futility is not unanimous, although most researchers agreed on 1-year survival as a cutoff. The majority of studies focused on single variables that can predict 1-year survival, employing either prospective or retrospective designs. Frailty was the major concept studied. Numerous predictive models have been identified, but no consensus was found.
Conclusion
Futility concepts generate interest in the TAVI procedure. In this review, numerous articles state that 1-year mortality serves as a cutoff to define futile procedures. Some variables, cardiac or otherwise, are independent predictors of 1-year mortality. Medical predictive models showed moderate sensitivity and specificity, except for machine learning, which shows promise for the future. However, few articles delve deeply into non-quantifiable parameters such as patient goals and objectives or ethical questions. More studies should focus on these parameters.

背景
经导管主动脉瓣植入术（Transcatheter Aortic Valve Implantation, TAVI）的临床应用规模正快速扩张，对主动脉狭窄患者的分层评估需求愈发深入。尤其在高危患者群体中，部分患者无法从TAVI中获得最优获益，甚至未获得任何临床收益，进而面临无效介入治疗的风险。尽管多位专家已就识别、预判此类无效介入的重要性达成共识，但TAVI无效性的定义及预测标准仍不明确。

研究目的
本研究旨在系统梳理现有针对TAVI无效性的定义、预测标准及医学预测模型的相关文献。

研究设计
本研究由两名研究人员开展范围综述（scoping review），并严格遵循PRISMA-ScR指南进行结果报告。

纳入排除标准
纳入所有探讨TAVI无效性的研究，涵盖其定义、预测变量及预测模型，不限研究设计类型；排除仅聚焦于外科瓣膜置换、瓣中瓣手术，或由钙化以外其他病理因素引发的主动脉狭窄的研究。

信息来源
研究从5个核心数据库中共检索到129项研究，分别为CINAHL、PUBMED、Cochrane图书馆、ClinicalTrials.gov及EMBASE。文献检索分两轮开展，分别于2024年2月及2024年10月进行，未对文献发表年份及研究语言设置限制。此外，通过交叉引用补充纳入了相关参考文献。

研究结果
目前学界对TAVI无效性的定义尚未达成统一共识，尽管多数研究者认可以1年生存率作为判定临界值。大多数研究聚焦于可预测1年生存率的单一变量，研究设计涵盖前瞻性及回顾性两种类型。衰弱是当前相关研究的核心概念。本综述已识别出多种预测模型，但尚未形成统一的标准。

研究结论
TAVI手术的无效性概念已引发学界广泛关注。本范围综述发现，诸多文献均主张以1年死亡率作为判定无效手术的临界值。部分心脏相关及非心脏相关变量可作为1年死亡率的独立预测因素。现有医学预测模型的灵敏度及特异度均处于中等水平，机器学习模型则展现出良好的应用前景。然而，鲜有研究深入探讨患者治疗目标、伦理问题等非量化参数，未来应加强此类方向的研究。