JAMA子刊:无症状主动脉瓣狭窄需年度复查这一指标,或能准确预测临床结局!

2022-02-18 MedSci原创 MedSci原创

在无症状的非严重AS患者中,随访1年时NT-proBNP浓度正常与低AVE和全因死亡率有关。

最近的研究对无症状非严重主动脉瓣狭窄(AS)患者的低风险状态提出了质疑。每年的N-末端脑钠肽(NT-proBNP)测量是否对风险评估有用尚不清楚。

为了评估年度NT-proBNP测量与非重度AS患者的临床结果的关系。来自丹麦哥本哈根大学医院心脏内科的专家设计了一项多中心、双盲的辛伐他汀和依折麦布治疗主动脉狭窄(SEAS)的随机临床试验中,对年度NT-proBNP浓度进行了分析。结果发表在JAMA Cardiology杂志上。

SEAS纳入了1873名不需要他汀类药物治疗的无症状AS患者,经主动脉最大流速为2.5-4.0米/秒,射血分数保留。该子研究包括1644名患者(87.8%),在基线和第1年都有血液样本。在第1年增加了年龄和性别调整的NT-proBNP浓度,以及从基线到第1年相对NT-proBNP浓度变化1.5倍或更大。主要结果是主动脉瓣事件(AVEs),即主动脉瓣置换、心血管死亡或因AS进展而导致的心力衰竭的综合情况。

在1644名患者中,996人为男性(60.6%);平均(SD)年龄为67.5(9.7)岁。在基线有NT-proBNP值的1594名患者中,有1228名(77.0%)调整后的NT-proBNP浓度在参考范围内(正常),在第1年的1644名患者中,有1164名(70.8%)在参考范围内。

在接下来的2年随访中,第1年正常与调整后的NT-proBNP水平上升的每100个患者年的AVE率为1.39(95%CI,0.86-2.23) vs 7.05(95%CI,4.60-10.81),轻度和中度AS的患者则分别为10.38(95%CI,8.56-12.59) vs 26.20(95%CI,22.03-31.15)(P < .01)。

与正常患者相比,轻度AS患者相应的全因死亡率为1.05(95% CI,0.61-1.81)vs 4.17(95% CI,2.42-7.19)(P < .01),中度AS患者为1.60(95% CI,0.99-2.57)vs 4.78(95% CI,3.32-6.87)(P < .01)。在多变量Cox比例危害回归模型中,在轻度AS患者(HR=8.12;95% CI,3.53-18.66;P < .001)和中度AS患者(HR=4.05;95% CI,2.84-5.77;P < .001)中,调整后NT-proBNP水平增加1年和NT-proBNP水平较基线变化1.5倍或以上的组合与最高AVE率有关。

该研究结果表明,在无症状的非严重AS患者中,随访1年时NT-proBNP浓度正常与低AVE和全因死亡率有关。相反,1年NT-proBNP水平增加,加上比基线增加50%或更多,可能与高AVE率有关。

 

参考文献:

Association of Annual N-Terminal Pro-Brain Natriuretic Peptide Measurements With Clinical Events in Patients With Asymptomatic Nonsevere Aortic Stenosis: A Post Hoc Substudy of the SEAS Trial. JAMA Cardiol. Published online February 16, 2022. doi:10.1001/jamacardio.2021.5916

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接受AVR的AS患者术前左心室充盈压升高是常见现象,无论其症状如何,均具有重要的预后意义。

拓展阅读

收缩期明显反流,“火眼金睛”辨真假主动脉瓣狭窄

本文结合我院的一个病例,患者既往查过心脏超声,患者提供的病史诉及主动脉瓣有关闭不全的情况,否认其他心脏病史。

JAHA:二尖瓣反流对主动脉狭窄患者血流动力学指标的影响

与单独的主动脉瓣狭窄相比,伴随的MR可降低MPG和正向流量。在评估主动脉瓣狭窄严重程度时,应仔细量化MR,以降低潜在的低估风险。

Circulation-Heart Failure:急性失代偿性心力衰竭患者主动脉狭窄的流行病学和结局

在经历过急性失代偿性心力衰竭住院治疗的患者中,主动脉狭窄很常见,预示着较差的死亡率结局。值得注意的是,在这一高危人群中,轻度/中度主动脉狭窄与1年死亡率独立相关。

容易忽视的隐形杀手!主动脉狭窄

主动脉狭窄为较常见的先天性动脉血管畸形,临床上易被忽略。在上海和北京统计的1085例先天性心脏血管病中占2.2%,在小儿病例中所占的比例更高,男女比例为(4~5): 1。

European Radiology:基于机器学习的CT-FFR对TAVR术严重主动脉狭窄患者决策的影响

现阶段,临床上推荐使用冠状动脉计算机断层扫描(CCTA)进行冠状动脉的解剖学评估以确定假体的大小,并指导入口部位和方法的选择,同时排除CAD。

Eur Heart J-Card Img:主动脉狭窄患者检测心脏淀粉样变的超声心动图指标

基于超声心动图检查的参数在检测AS患者CA方面有很大的前景。进一步的研究应该探索这些超声心动图变量的最佳临界值,以获得更好的诊断准确性。