Moreno Yangüela M, López-Sendón J
Instituto de Cardiología, Madrid.
Rev Port Cardiol. 1990 Mar;9(3):247-59.
Doppler echocardiography, providing objective data on heart anatomy and cardiac function, is a diagnostic method of unquestionable value in the acute phase of myocardial infarction. In what concerns myocardial infarction complications; echocardiography permits: a) evaluation of ventricular function, by quantifying heart failure and establishing the diagnosis of ventricular aneurysm; b) it is the most reliable method in the diagnosis of thrombi, and c) it constitutes a fundamental diagnostic tool in mechanical complications: rupture of the heart structures and evaluation of valvular competence. a) Evaluation of ventricular function. The analysis of ventricular dimensions and segmentary wall motion abnormalities permits the quantification of the infarct size and its repercussion upon the cardiac function. Otherwise, left ventricular proto and end diastolic filling rates give an idea about ventricular diastolic function alterations. b) Ventricular thrombi. The incidence of ventricular thrombi in AMI is variable, depending on the site of infarction and the number of segments with wall motion abnormalities. By echocardiography it has been demonstrated that 40% of the anterior transmural myocardial infarctions and 10% of the inferior ones disclosed thrombi, although the incidence of systemic embolism is scarce and similar on both anterior and inferior infarctions: nearly 2% during the first month after infarction. The criteria that identify the embolic risk include: thrombus size over 2 x 2 x 2 cm, pediculated and mobile thrombi. On the other hand, right intraventricular thrombi incidence is rare nearly 5% of right ventricular infarctions and post-infarction pulmonary embolism is probably more related to peripheral venous thrombus than to an intraventricular one. c) Mechanical complications. Echocardiography enables the direct diagnosis of interventricular septum and papillary muscles rupture in about 80% of the cases and although ordinary does not provide direct data on free ventricular wall rupture, the detection of pericardial effusion with high density echoes, together with finding of free right ventricular and atrial wall collapse, gives 80% of sensibility and over 90% of specificity in the diagnosis of free ventricular wall rupture. Finally, Doppler echocardiography permits the diagnosis and quantification of mitral and tricuspid regurgitation secondary to a rupture of even a simple disfunction of the atrioventricular subvalvular apparatus.
多普勒超声心动图可提供有关心脏解剖结构和心脏功能的客观数据，在心肌梗死急性期是一种具有无可置疑价值的诊断方法。在心肌梗死并发症方面，超声心动图可用于：a）通过量化心力衰竭和诊断室壁瘤来评估心室功能；b）是诊断血栓最可靠的方法；c）是诊断机械性并发症（心脏结构破裂和评估瓣膜功能）的重要诊断工具。a）心室功能评估。分析心室大小和节段性室壁运动异常可量化梗死面积及其对心脏功能的影响。此外，左心室舒张早期和末期充盈率可反映心室舒张功能的改变。b）心室血栓。急性心肌梗死时心室血栓的发生率各不相同，取决于梗死部位和室壁运动异常节段的数量。超声心动图显示，40%的前壁透壁性心肌梗死和10%的下壁心肌梗死可发现血栓，尽管系统性栓塞的发生率很低，在前壁和下壁梗死中相似：梗死后头一个月内接近2%。识别栓塞风险的标准包括：血栓大小超过2×2×2cm、有蒂且可移动的血栓。另一方面，右心室内血栓的发生率很低，约占右心室梗死的5%，梗死后期的肺栓塞可能更多与外周静脉血栓有关，而非心室内血栓。c）机械性并发症。超声心动图能够直接诊断约80%的室间隔和乳头肌破裂病例，虽然通常不能提供有关心室游离壁破裂的直接数据，但检测到高密度回声的心包积液，以及发现右心室和心房游离壁塌陷，在诊断心室游离壁破裂时具有80%的敏感性和超过90%的特异性。最后，多普勒超声心动图可诊断和量化继发于房室瓣下装置破裂或甚至简单功能障碍的二尖瓣和三尖瓣反流。
