呼吸对慢性阻塞性肺病左心室充盈的影响及其机制的超声心动图研究

目的探讨超声心动图检测慢性阻塞性肺病（COPD）患者左心室功能和COPD病程的可行性。方法采用Sequoia512彩色超声诊断仪,记录21例COPD患者及50名健康人自然呼吸时二尖瓣口E峰、A峰血流速度,同步记录心电图和呼吸曲线,计算二尖瓣舒张早期E峰血流速度呼吸性波动指数（RVI）及E峰与A峰血流速度比值（E/A）呼吸变化率。结果两组均表现为E峰血流速度、E/A吸气相低于呼气相（P〈0.001）;COPD组A峰血流速度吸气相与呼气相差异无统计学意义（P=0.076）,而健康对照组A峰血流速度吸气相低于呼气相（P〈0.001）。COPD组二尖瓣E峰血流速度RVI及E/A呼吸变化率均较对照组增大（P=0.002）。结论自然呼吸对COPD患者二尖瓣血流影响具有规律性,进一步验证了呼吸影响心功能机制新假说,同时也为利用多普勒技术评价COPD患者左室功能损害程度和肺实质病变严重程度的进一步研究提供更多信息。

Echocardiographic study on the effects of respiration on left ventricular filling and the mechanism in chronic obstructive pulmonary disease

Objective To study the feasibility of examining the left ventricular function and course of chronic obstructive pulmonary disease(COPD) by echocardiography.Methods Pulsed-wave Doppler spectra of transmitral flow were recorded with Sequoia 512 in 50 normal subjects and 21 COPD patients.Electrocardiogram and respiratory tracing were recorded simultaneously.E wave and A wave of transmitral flow were measured.Then the respiratory variation indices (RVI) of the E wave in early diastolic phase of mitral valve were calculated The respiratory variation rate during inspiration and expiration about ratios of velocity of E wave to A wave(E/A) of transmitral flow were calculated.Results During natural inspiration,the peak E velocity and E/A of mitral valve in COPD patients and control group were both decreased (P<0.001).There was no significant change about the peak A velocity of mitral valve between inspiration and expiration in COPD patients (P=0.076),but in control group,the peak A velocity of mitral valve decreased during inspiration (P<0.001),and both of the changes of peak E velocity and E/A during respiration in COPD patients were obviously than those in control group(P=0.002).Conclusions The effects of natural respiration on transmitral Doppler flow are partly regular in COPD patients,this study proves the accuracy of the new hypothesis of the mechanism of respiration effects on hemodynamics.It would supply more information in evaluating left ventricular filling in COPD patients.