Background:Grading of severe (aortic valve area ≤1 cm²) aortic stenosis with preserved left ventricular ejection fraction is based on a classification depending on flow (normal flow versus low flow) and pressure gradient (low gradient versus high gradient). The aim of the present study was to compare the outcome of patients with normal flow high gradient and low flow high gradient severe aortic stenosis (SAS) with no or minimal symptoms.Methods:This multicenter study enrolled 983 consecutive patients (mean age 75±11 years, 459 women) with asymptomatic or minimally symptomatic HG (mean pressure gradient ≥40 mm Hg) SAS with preserved left ventricular ejection fraction. Low flow was defined by Doppler echocardiography as a stroke volume index <30 mL/m² (n=131) or a stroke volume <55 mL (n=136). The end point was all-cause mortality.Results:During a median follow-up period of 48 (45–52) months, 225 patients (23%) died. The 60–month mortality was higher in low flow high gradient SAS compared with normal flow high gradient SAS (36±5% versus 22±2% and 38±5% versus 21±2% for stroke volume index and stroke volume, respectively, both P<0.0001). After adjustment for outcome predictors including aortic valve replacement as time-dependent covariate, low flow high gradient SAS displayed considerable mortality risk during follow up compared with normal flow high gradient SAS (adjusted HR 2.17 [1.51–3.13]; P<0.0001 for stroke volume index <30 mL/m² and adjusted HR 1.86 [1.29–2.68]; P=0.001, for stroke volume <55 mL). The prognostic impact of low flow was consistent in subgroups of patients.Conclusions:Asymptomatic or minimally symptomatic patients with low flow high gradient SAS and preserved left ventricular ejection fraction have a considerable increased risk of mortality during follow-up. These patients should be promptly considered for aortic valve replacement.

中文翻译：

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低血流对高门脉梯度严重主动脉瓣狭窄和保留左心室射血分数的患者的预后价值：一项多中心研究。

背景：严重的（主动脉瓣面积≤1cm ²）主动脉瓣狭窄伴左心室射血分数得以保留，其分级取决于血流（正常血流与低血流）和压力梯度（低血流与高血流）的分类。本研究的目的是比较无或有轻微症状的正常血流高梯度和低血流高梯度严重主动脉瓣狭窄（SAS）患者的结果。方法：该多中心研究招募了983例连续患者（平均年龄75±11）岁，459名女性）无症状或轻微症状性HG（平均压力梯度≥40 mm Hg）SAS，左心室射血分数保留。多普勒超声心动图将低流量定义为卒中体积指数<30 mL / m ²（n = 131）或每搏量<55 mL（n = 136）。终点是全因死亡率。结果：在中位随访期48（45-52）个月中，有225例患者（23％）死亡。与正常流量高梯度SAS相比，低流量高梯度SAS的60个月死亡率更高（每搏量指数和每搏量分别为36±5％，22±2％和38±5％对21±2％，两者P <0.0001）。在对包括主动脉瓣置换作为时间相关协变量在内的结果预测因素进行调整后，与正常流量高梯度SAS相比，低流量高梯度SAS在随访期间显示出相当大的死亡风险（校正后的HR 2.17 [1.51-3.13]；对于卒中量，P <0.0001指数<30 mL / m ²，调整后的HR 1.86 [1.29–2.68]；P对于中风量<55 mL，= 0.001）。结论：低流量高梯度SAS并保留左心室射血分数的无症状或轻度症状患者在随访期间死亡风险显着增加。这些患者应及时考虑更换主动脉瓣。