煙草 敏¹, 原田 昌彦¹, 宮坂 匠¹, 吉川 浩一¹, 寳田 雄一¹, 桝谷 直司¹, 林 京子¹, 原 文彦²

Satoshi TABAKO¹, Masahiko HARADA¹, Takumi MIYASAKA¹, Koichi YOSHIKAWA¹, Yuichi TAKARADA¹, Naoji MASUYA¹, Kyoko HAYASHI¹, Fumihiko HARA²

¹東邦大学医療センター大森病院臨床生理機能検査部, ²東邦大学医療センター大森病院循環器内科

¹Department of Clinical Functional Physiology, Toho University Omori Medical Center, ²Department of Cardiovascular Medicine, Toho University Omori Medical Center

キーワード : left ventricular diastolic function, left ventricular mass index, left atrial volume index, Doppler echocardiography, hypertension

背景：高血圧性心疾患では拡張不全の頻度が高く，左室拡張能の評価は臨床的に重要である．本研究の目的は，高血圧患者の年代別拡張能評価に際して，従来のドプラ法による拡張能指標に加え，左室拡張能と左房容積との関連性について検討すること．対象と方法：対象は，30‐80歳代の高血圧患者522例（平均年齢：62歳，男性285例）．パルスドプラ法で左室流入拡張早期波（E），心房収縮波（A），組織ドプラ法で拡張早期僧帽弁輪部速度（e’）を計測した．心尖部二腔断面及び四腔断面（biplane Simpson法）より求めた左房容積を体表面積で補正し左房容積係数（LAVI），Mモード法あるいは断層計測から，米国心エコー図学会（ASE）の式で求めた左室心筋重量より左室心筋重量係数（LVMI）を算出した．心房細動例，虚血性心疾患例，中等度以上の僧帽弁逆流症例は除外した．結果：高血圧患者における年代別LAVIでは全ての年代で有意差を認めなかった．ASEのガイドラインに基づいて，高血圧患者を，左房拡大なし（LAVI＜29 ml/m²）；HT-LAD（-）群，左房拡大あり（LAVI≧29 ml/m²）；HT-LAD（＋）群の2群に分類した．多くの年代において，健常群（280例）に比べて高血圧患者群の拡張能は低下し，HT-LAD（-）群よりもHT-LAD（＋）群においてe’は低値，E/e’は高値であった．また，E/e’とLAVI（r＝0.59，p＜0.0001），E/e’とLVMI（r＝0.59，p＜0.0001）で有意な相関を認めた．30‐50歳台で左房拡大を伴った高血圧患者の左室拡張障害は，20歳程進行しており，降圧管理の重要性が示唆された．結論：高血圧患者においてLAVIは加齢による影響が少ないことから，従来の拡張能指標に左房容積計測を加味することで，より正確な拡張能評価が可能であると思われる．

Background: Hypertensive heart disease is associated with a high incidence of diastolic heart failure, making evaluation of left ventricular (LV) diastolic function clinically important. The purpose of this study was to examine the diastolic paramerers using conventional Doppler imaging and those relations with left atrial (LA) volume when evaluating diastolic function in patients with hypertension. Subjects and Methods: We studied 522 patients with hypertension ranging in age from their 30’s to their 80’s (mean±SD, 61.8±14.7 years). Peak mitral flow velocity of the early rapid filling wave (E) and the late filling wave resulting from atrial contraction (A) were calculated by pulsed Doppler echocardiography; and early diastolic mitral annular velocity (e’), by tissue Doppler imaging. LA volume calculated from the apical two- and four-chamber views (biplane Simpson’s method) was corrected for body surface area and the LA volume index (LAVI) was calculated. The LV mass index (LVMI) was also calculated from LV mass analyzed using the American Society of Echocardiography (ASE) equation of the M-mode echocardiographic method or fault measurement. Patients with atrial fibrillation, ischemic heart disease, and moderate-to-severe mitral regurgitation were excluded. The two hundred eighty subjects comprising the control group had normal blood pressure and normal results on echocardiographic examination, including LV dimension and systolic function. Results: The LAVI of patients with hypertension showed no significant generational differences. Patients with hypertension were classified into two groups; HT-LAD (-) group: those with hypertension (LAVI<29ml/m²); HT-LAD (+) group: those with hypertension (LAVI>=29ml/m²). In most generations, diastolic dysfunction was more advanced in the hypertensive group than in the control group. In addition, e’ was lower and E/e’ higher in the HT-LAD (+) group than in the HT-LAD (-) group. Further, the correlation between E/e’ and LAVI (r=0.59, p<0.0001) and E/e’ and LVMI (r=0.59, p<0.0001) was significant. LV diastolic function in patients in their 30’s and 50’s with LA enlargement and hypertension is progressing about 20 years,suggested importance of antihypertensive management. Conclusion: LA volume measurement in patients with hypertension may prove useful in evaluating diastolic function more accurately.