辻本 悟史, 宮坂 陽子, 諏訪 惠信, 前羽 宏史, 塩島 一朗

Satoshi TSUJIMOTO, Yoko MIYASAKA, Yoshinobu SUWA, Hirofumi MAEBA, Ichiro SHIOJIMA

関西医科大学第二内科循環器内科

Division of Cardiology, Department of Medicine II, Kansai Medical University, Japan

キーワード :

【Background】
Improving the identification of patients with asymptomatic aortic stenosis （AS） at high risk of cardiac events is a challenging issue. We sought to evaluate the predictors of adverse outcome in patients with asymptomatic severe AS.
【Methods】
We identified patients with asymptomatic severe AS （aortic valve area ＜1.0 cm² and/or peak velocity ＞=4.0 m/s） and preserved left ventricular ejection fraction （EF） （EF＞=50％） in 2007-2011, and followed them to adverse clinical event or last follow-up until November 2012. Adverse clinical event was defined as non-fatal myocardial infarction, congestive heart failure, aortic valve replacement, or all-cause death. Cox-proportional hazards modeling was used to assess the risk of adverse outcome.
【Results】
Of 82 consecutive patients with asymptomatic severe AS and preserved left ventricular EF （74±10 year-old, 43％ men, EF 71±8 ％, indexed aortic valve area 0.60±0.14 cm², indexed left ventricular mass 115±36 g/m², 68％ hypertension, 16％ diabetes）, 33 patients （40％） had an adverse clinical event during a mean follow-up of 24±19 months （non-fatal myocardial infarction in 3 patients, congestive heart failure in 9 patients, aortic valve replacement in 15 patients, and all-cause death in 6 patients）. Adverse clinical event was not associated with age （P= 0.36） or sex （P= 0.15）. In a multivariate Cox-proportional hazards model, higher indexed left ventricular mass （per 10 g/m²; Hazard ratio=1.14, 95％ confidence interval=1.03 -1.26, P=0.01）, and lower indexed aortic valve area （Hazard ratio=0.01, 95％ confidence interval=.001-0.20, P＜0.01） were independent predictors of adverse outcome, independent of other comorbidities.
【Conclusions】
In asymptomatic patients with severe AS, comprehensive echocardiographic assessment of left ventricular mass and aortic valve area improve risk stratification, independent of other prognostic covariates.