背景:中度主动脉瓣狭窄(AS)的不良结局可能由进展为重度AS或合并症的影响引起。在缺乏支持中度AS患者主动脉瓣置换术(AVR)的随机试验证据的情况下,根据风险对患者进行表型分析可能有助于决策。
目的:本研究旨在确定和验证可用于指导患者管理的中度AS集群。
方法:将无监督聚类算法应用于人口统计,合并症,中度AS患者训练数据集中的超声心动图参数(n=2,469)。通过将定义的聚类分配给中度AS的独立组(n=1,358)来获得外部验证。主要结果,心脏死亡的复合物,心力衰竭住院,或主动脉瓣(AV)介入5年后,在两个数据集中的集群之间进行评估。
结果:四个不同的簇-心血管(CV)-共病,低流量,钙化房室,和低风险和显著结果(两个数据集的对数秩P<0.0001)被识别并重复。风险最高的是CV-合并症组(验证HR:2.00[95%CI:1.54-2.59];P<0.001)。AVR对心脏死亡的影响在集群之间不同。钙化房室群中AVR后的结局率显着降低(验证HR:0.21[95%CI:0.08-0.57];P=0.002),但对其他3个集群的结果没有显著影响。这些分析受到低AVR率的限制。
结论:中度AS有几种表型,多种合并症是中度AS患者不良结局的关键驱动因素.在这些组中,AVR未改变非钙化中度AS患者的预后。仔细注意中度AS的亚组对于定义可治疗的风险可能很重要。
BACKGROUND: Adverse outcomes from
moderate aortic stenosis (AS) may be caused by progression to severe AS or by the effects of comorbidities. In the absence of randomized trial evidence favoring aortic valve replacement (AVR) in patients with moderate AS, phenotyping patients according to risk may assist decision making.
OBJECTIVE: This study sought to identify and validate clusters of
moderate AS that may be used to guide patient management.
METHODS: Unsupervised clustering algorithms were applied to demographics, comorbidities, and echocardiographic parameters in a training data set in patients with moderate AS (n = 2,469). External validation was obtained by assigning the defined clusters to an independent group with moderate AS (n = 1,358). The primary outcome, a composite of cardiac death, heart failure hospitalization, or aortic valve (AV) intervention after 5 years, was assessed between clusters in both data sets.
RESULTS: Four distinct clusters-cardiovascular (CV)-comorbid, low-flow, calcified AV, and low-risk-with significant outcomes (log-rank P < 0.0001 in both data sets) were identified and replicated. The highest risk was in the CV-comorbid cluster (validation HR: 2.00 [95% CI: 1.54-2.59]; P < 0.001). The effect of AVR on cardiac death differed among the clusters. There was a significantly lower rate of outcomes after AVR in the calcified AV cluster (validation HR: 0.21 [95% CI: 0.08-0.57]; P = 0.002), but no significant effect on outcomes in the other 3 clusters. These analyses were limited by the low rate of AVR.
CONCLUSIONS: Moderate AS has several phenotypes, and multiple comorbidities are the key drivers of adverse outcomes in patients with
moderate AS. Outcomes of patients with noncalcified
moderate AS were not altered by AVR in these groups. Careful attention to subgroups of
moderate AS may be important to define treatable risk.