Iqbal Mobeen, Ahmed Raees, Al Balas Hassan, Gharard Salah Uddin, Alotaibi Fahad D
Department of Pulmonology, King Abdulaziz National Guard Hospital, Alhasa, Kingdom of Saudi Arabia.
J Coll Physicians Surg Pak. 2006 May;16(5):320-3.
To determine the correlation and diagnostic utility of impaired left atrial emptying fraction, an indicator of diastolic dysfunction, with raised intravascular volume determined by vascular pedicle width on upright postero-anterior chest roentgenogram.
Cohort study.
Department of Medicine, King Abdulaziz National Guard Hospital, Alhasa, Saudi Arabia from October till December 2002.
Thirty-two out of 56 patients with normal systolic function (ejection fraction >50%) on echocardiogram were included in the study. Left atrial dimensions were measured at the end of left ventricular diastole (LADed) and systole (LADes) on M-mode tracing. Left atrial emptying fraction (LAEF) was calculated by dividing LADed by LADes. Ratio of peak early diastolic velocity (E/A) to peak late diastolic velocity, isovolemic relaxation time (IVRT) and deceleration time of E-wave (DT) were also recorded on transmitral Doppler signal. Postero-anterior views of chest X-rays done within 48 hours of echocardiogram were studied for the measurement of vascular pedicle width (VPW) and cardiothoracic ratio (CTR). Univariate and multiple regression analysis were performed to identify possible predictors of VPW. Receiver operator curves were constructed to see diagnostic utility of impaired LAEF for raised intravascular volume measured by VPW.
Mean age for the patients was 58.56 +/- 17 years. There were 15 females (46.9%) and 17 males (54.1%). LADes, LADed, LAEF and DT were 2.89 +/- 0.63 cm, 3.81 +/- 0.53 cm, 0.75 +/- 0.10 and 202 +/- 49.9 msec respectively. VPW and CTR were 55.81 +/- 10.2 mm and 0.54 +/- 0.08. Significant independent predictors of VPW on univariate regression analysis were entered into multiple regression models, which revealed LAEF and DT as the only predictors of VPW. The final regression equation was VPW = 15.43 + 35.7 (LAEF) + 0.06 (DT), R2 = 0.35, p = 0.0008. LAEF > 0.75 had a sensitivity of 74% and specificity of 94% for diagnosing raised intravascular volume defined as VPW > 53 mm.
LAEF > 0.75 is a reliable indicator of intravascular volume expansion in patients with normal systolic function signifying diastolic dysfunction and activation of salt and water retaining mechanisms.
确定舒张功能障碍指标左心房排空分数降低与通过立位后前位胸部X线片上血管蒂宽度测定的血管内容量增加之间的相关性及诊断效用。
队列研究。
沙特阿拉伯艾哈萨阿卜杜勒阿齐兹国王国民警卫队医院内科，2002年10月至12月。
56例超声心动图显示收缩功能正常（射血分数>50%）的患者中，32例纳入研究。在M型超声心动图上测量左心室舒张末期（LADed）和收缩末期（LADes）的左心房内径。左心房排空分数（LAEF）通过LADed除以LADes计算得出。还记录了二尖瓣血流频谱上舒张早期峰值速度（E/A）与舒张晚期峰值速度之比、等容舒张时间（IVRT）及E波减速时间（DT）。对在超声心动图检查后48小时内拍摄的胸部X线后前位片进行研究，测量血管蒂宽度（VPW）和心胸比率（CTR）。进行单因素和多因素回归分析以确定VPW的可能预测因素。构建受试者工作特征曲线以观察LAEF降低对通过VPW测量的血管内容量增加的诊断效用。
患者平均年龄为58.56±17岁。女性15例（46.9%），男性17例（54.1%）。LADes、LADed、LAEF及DT分别为2.89±0.63cm、3.81±0.53cm、0.75±0.10及202±49.9毫秒。VPW及CTR分别为55.81±10.2mm及0.54±0.08。单因素回归分析中VPW的显著独立预测因素被纳入多因素回归模型，结果显示LAEF和DT是VPW的唯一预测因素。最终回归方程为VPW = 15.43 + 35.7（LAEF）+ 0.06（DT），R2 = 0.35，p = 0.0008。对于诊断血管内容量增加（定义为VPW>53mm），LAEF>0.75的敏感度为74%，特异度为94%。
LAEF>0.75是收缩功能正常患者血管内容量扩张的可靠指标，提示舒张功能障碍及水钠潴留机制激活。
