原田 昌彦¹, 煙草 敏¹, 林 京子¹, 寳田 雄一¹, 藤井 悠一郎², 原 文彦², 山崎 純一²

Masahiko HARADA¹, Satoshi TABAKO¹, Kyoko HAYASHI¹, Yuichi TAKARADA¹, Yuichiro FUJII², Fumihiko HARA², Junichi YAMAZAKI²

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 Medical Center Omori Hopital, ²Department of Cardiovascular Medicine, Toho University Medical Center Omori Hopital

キーワード : left ventricular diastolic function, atrial fibrillation, color kinesis, Doppler echocardiography, B-type natriuretic peptide

目的：Color kinesis（CK）法で心房細動（Af）患者の拡張能評価が可能か脳性ナトリウム利尿ペプチド（BNP）値との関連より検討すること．対象と方法：心エコー検査同日に血中BNP測定が行えたAf46例（男性22例，平均64±12歳），使用装置はPhilips社製 Sonos7500，左室短軸像乳頭筋レベルで拡張期CK画像を記録し，解析はYD社製ICKソフトを用いた．左室局所において拡張早期30％時間の面積比率を％表示，これをCK-diastolic index（CK-DI）とし，左室6分割の平均をmean CK-DIとした．ドプラ法で左室急速流入波（E）とその減衰時間（DT），拡張早期僧帽弁輪速度（e´）を計測した．実測値BNP値は自然対数変換（log BNP）し，各指標との関連を検討した．結果と考察：6例はCK画像描出不良のため解析が困難であった．残り40例の検討で，log BNPとの相関は，mean CK-DI（r＝-0.55，p＜0.001）），e´（r＝-0.46，p＜0.01），E/e´（r＝0.44，p＜0.01），DT（r＝-0.15）と，最も良好な相関を示したのはmean CK-DIであった．解析に用いた心拍のRR間隔は平均889±162 ms，先々行と先行RR間隔との比は平均1.0±0.2であった．結論：CK法は，Af患者の拡張能評価に応用出来る可能性がある．

Background: Color kinesis (CK), a technique based on acoustic quantification, has been developed to facilitate the evaluation of regional wall motion and left ventricular (LV) function. Recently it has been reported that plasma B-type natriuretic peptide (BNP) level is associated with LV diastolic dysfunction. The purpose of this study is to examine the feasibility of CK in evaluating LV diastolic function in patients with atrial fibrillation (AF). Subjects and Methods: Forty-six patients (mean age: 64±12 years) with AF were referred for echocardiography to evaluate cardiac function with simultaneous measurements of the plasma BNP. Echocardiography was performed for assessment of LV function, including LV ejection fraction (EF), early mitral peak flow (E), deceleration time of E (DT), early diastolic mitral annular velocity (e´), and diastolic CK. Diastolic CK images, obtained from the LV mid-papillary short-axis view, were analyzed by using ICK software. The CK-diastolic index (CK-DI) was defined as the calculated LV segmental filling fraction during the first 30% of diastole, expressed as a percentage. The mean CK-DI was determined from the average CK-DI of six segments (anterior, anteroseptal, septal, inferior, posterior, lateral wall). Results: Six cases were excluded from the analysis because of poor CK images. We found significant correlations between mean CK-DI and log BNP (r=-0.55, p〈0.001), whereas log BNP correlated weakly with E/e´ (r=0.44), EF (r=-0.21), and DT (r=-0.15). Conclusion: The analysis of diastolic CK may be useful for quantitative assessment of LV diastolic function in patients with AF.