低剂量多巴酚丁胺超声心动图测量左室收缩功能的研究

本研究应用低剂量多巴酚丁胺负荷超声心动图（ＬＤＤＳＥ）在４１例二尖瓣返流（ＭＲ）患者探讨评价心脏收缩功能的可靠性指标。结果显示：静息状态二尖瓣病变合并ＭＲ组（Ａ组）和继发于心肌病的ＭＲ组（Ｂ组）ｄｐ／ｄｔｍａｘ均降低，Ａ组ＥＦ正常，Ｂ组ＥＦ亦降低；ＬＤＤＳＥ后，Ａ组ｄｐ／ｄｔｍａｘ显著增加（Ｐ＜０．０１）至正常水平，Ｂ组亦增加（Ｐ＜０．００１），但仍低于正常，两组ＥＦ值均显著增加（Ｐ＜０．０１）。本研究表明静息状态ＥＦ正常的伴二尖瓣返流的心脏病患者可存在心肌收缩功能减退，如果ＬＤＤＳＥ能够改善这部分患者的心肌收缩性，则心功能损害为可逆性的，ｄｐ／ｄｔｍａｘ可做为评价ＭＲ患者心肌收缩性的敏感性指标，这将为外科手术适应症的选择及判断预后提供依据

Effect of Low Dose Dobutamine Echocardiography on Left Ventricular Systolic Function in Mitral Regurgitation

To explore the reliable method of assessing the left ventricular systolic function in patients with mitral regurgitation(MR),echocardiography at baseline and low dose dobutamine stress echocardiography(LDDSE)were performed in 41 cases with MR.The results:before LDDSE there were lower normal level dp/dtmax in mitral valve lesions with MR(group A)and dilated or ischemic myocardiopathy(group B),EF was normal in group A and decreased in group B.During LDDSE dp/dtmax significantly increased to normal level(P<0 01)in group A,increased but still below normal level dp/dtmax was also detected in group B(P<0 001).EF were higher than that before LDDSE.at both groups.The study indicated there is impaired myocardial contractile function in patients with MR with normal EF.Reversible impaired myocardial contractile function are existed in those patients with improved heart function by LDDSE,dp/dtmax is a reliable and sensitive parameter for evaluating myocardial systolic function in patients with MR.