本間 博¹, 大野 忠明¹, 時田 祐吉¹, 松崎 つや子², 藤本 啓志¹, 吉永 綾¹, 佐藤 丞子¹, 横島 友子¹, 伊藤 恵子¹, 水野 杏一¹

Hiroshi HONMA¹, Tadaaki OHNO¹, Yukichi TOKITA¹, Tsuyako MATSUZAKI², Hiroyuki FUJIMOTO¹, Aya YOSHINAGA¹, Shoko SATO¹, Tomoko YOKOSHIMA¹, Keiko ITO¹, Kyoichi MIZUNO¹

¹日本医科大学循環器内科, ²日本医科大学付属病院生理機能センター

¹Division of Cardiology, Department of Internal Medicine, Graduate School of Medicine, ²Laboratory of Ultrasonography, Nippon Medical School Hospital

キーワード : aortic stiffness, aortic valve calcification, left ventricular diastolic function, chronic kidney dysfunction

目的：本研究の目的は大動脈弁石灰化（aortic valve calcification: AVC）と胸部上行大動脈（thoracic ascending aorta: TAA）近位部の硬度上昇との関係を明らかにし，それらの左室（left ventricular: LV）機能および腎機能に対する影響を調べることである．方法：糖尿病32人，脂質異常症60人を含む計138人の高血圧患者をAVCの重症度に応じて4群に分けた．TAA近位部の弾性度を組織ドプライメージング法に基づいて計測したストレインレートの指標（最大ストレインレート値［SR（+）］，最小SR値［SR（-）］およびQRSピークからTAA近位部SR（-）までの時間〔SRT〕）を分析した．結果：SR（+）およびSRTは中等度のAVCを有する患者で軽度のAVCを有する患者よりも有意に高値であった．SRTおよびSR（-）は年齢，大動脈弁位での最大血流速度，TAA壁の厚さ（IMC），左室拡張能および腎機能とよく相関した．SRTはIMC，脂質異常症および左室拡張機能と独立した相関を認めた．結論：AVCの重症度はTAA近位部の弾性度と相関が認められた．SR指標はAVCを有する患者においてTAAの硬度と左室機能および腎機能との関係を評価するのに有用である．

Purpose: The aim of this study was to clarify the relationship between the severity of aortic valve calcification (AVC) and stiffness of the proximal thoracic ascending aorta (TAA), and to examine their influence on left ventricular (LV) function and renal function. Methods: A total of 138 hypertensive patients including 32 with diabetes mellitus and 60 with dyslipidemia were divided into four groups based on the severity of AVC. We analyzed the elastic properties of the proximal TAA from the following strain-rate indices based on tissue Doppler imaging: maximum strain rate [SR(+)], minimum SR [SR(-)], and the time between the QRS peak and the peak SR(-) of the proximal TAA (SRT). Results: SR(+) and SRT were significantly greater in patients with moderate AVC than in patients with mild AVC. SRT and SR(-) were well correlated with age, peak velocity across AV, TAA wall thickness (IMC), LV diastolic function, and renal function. SRT was independently related to IMC, dyslipidemia, and LV diastolic function. Conclusion: The severity of AVC was correlated with the elastic properties of the proximal TAA. The SR indices are useful for assessing the relation of TAA stiffness to LV function and renal function in patients with AVC.