Division of Cardiology, Korea University College of Medicine, Seoul, Korea.
J Am Soc Echocardiogr. 2010 Mar;23(3):309-14. doi: 10.1016/j.echo.2009.12.019.
The purpose of this study was to determine whether atrial electromechanical conduction time (EMT) measured by echocardiography can predict 6-month maintenance of sinus rhythm (SR) after electrical cardioversion in patients with atrial fibrillation (AF).
Fifty-three patients with persistent AF (>1 month) who had successful cardioversion and 30 controls with SR were prospectively enrolled. SR maintenance was assessed during 6-month follow-up. EMT was measured as the time interval from the onset of the P wave on electrocardiography to the peak of the late diastolic wave from the septal and lateral mitral annulus (EMT-S and EMT-L, respectively) and the lateral tricuspid annulus (EMT-T) on tissue Doppler echocardiography.
Compared with controls, left atrial (LA) volume index, P-wave duration, and EMT were significantly larger in patients with AF (all P values<.001). In patients with AF, the duration of AF (P=.71) and P-wave duration (P=.24) were not different between the SR maintenance group (n=23) and the AF recurrence group (n=30), and there was a trend toward increased LA volume index in the AF recurrence group (47.0+/-12.4 vs 45.3+/-12.6 mL/m2, P=.07). EMT-S and EMT-L were significantly larger in the AF recurrence group (131.4+/-20.9 vs 116.3+/-15.5 ms, P=.005, and 152.2+/-15.7 vs 128.9+/-13.8 ms, P<.001, respectively), but not EMT-T. EMT-S and EMT-L were related to LA volume index (r=.36, P=.008, and r=.33, P=.02, respectively). On multivariate logistic regression analysis, only EMT-L was an independent predictor of identifying patients who remained in SR (P<.001), and the sensitivity and specificity for the prediction of 6-month maintenance of restored SR were 82.6% and 83.3% using a cutoff value of EMT-L<or=138.0 ms (odds ratio, 0.862; 95% confidence interval, 0.788-0.942; P=.001).
LA EMT was significantly prolonged in patients with recurring AF, indicating significantly depressed atrial conduction in enlarged LA, and can predict 6-month maintenance of SR after electrical cardioversion.
本研究旨在探讨通过超声心动图测量的心房机电传导时间（EMT）能否预测心房颤动（AF）患者电复律后 6 个月窦性心律（SR）的维持情况。
前瞻性纳入 53 例持续性 AF（>1 个月）且复律成功的患者和 30 例 SR 患者作为对照组。在 6 个月的随访期间评估 SR 维持情况。通过组织多普勒超声心动图测量心电图 P 波起始至间隔和外侧二尖瓣环舒张晚期波峰（EMT-S 和 EMT-L）和外侧三尖瓣环（EMT-T）的时间间隔来测量 EMT。
与对照组相比，AF 患者的左心房（LA）容积指数、P 波持续时间和 EMT 明显更大（均 P<.001）。在 AF 患者中，AF 持续时间（P=.71）和 P 波持续时间（P=.24）在 SR 维持组（n=23）和 AF 复发组（n=30）之间无差异，且 AF 复发组 LA 容积指数呈增加趋势（47.0+/-12.4 vs 45.3+/-12.6 mL/m2，P=.07）。AF 复发组的 EMT-S 和 EMT-L 明显更大（131.4+/-20.9 vs 116.3+/-15.5 ms，P=.005，和 152.2+/-15.7 vs 128.9+/-13.8 ms，P<.001），但 EMT-T 则不然。EMT-S 和 EMT-L 与 LA 容积指数相关（r=.36，P=.008，和 r=.33，P=.02）。多变量逻辑回归分析显示，仅 EMT-L 是预测 SR 维持的独立指标（P<.001），当 EMT-L<or=138.0 ms 时，预测 6 个月恢复 SR 的敏感性和特异性分别为 82.6%和 83.3%（优势比，0.862；95%置信区间，0.788-0.942；P=.001）。
复发性 AF 患者的 LA EMT 明显延长，提示 LA 扩大时心房传导明显抑制，可预测电复律后 6 个月 SR 的维持情况。
