DK2985_C000 1..28 - AlSharqia Echo Club

178 Transesophageal Echocardiography(A)BEFORE CPB(B)AFTER CPB(C)LARARVLV(D)SYSTOLE(E)SYSTOLE(F)LVSYSTOLE(G)DIASTOLE(H)DIASTOLEDIASTOLEFigure 8.24 Severe acute right ventricular ischemic dysfunction in a 71-year-old woman after cardiopulmonary bypass (CPB). Thefour-chamber view demonstrates the new appearance of acute right ventricular dilatation (A–C) and inferior wall akinesis on the transgastricmid-papillary view indicated with the dotted line (D–H) (LA, left atrium; LV, left ventricle; RA, right atrium; RV, right ventricle).the contour of the proximal anteroseptal wall in the longaxisview and a segmental dilation in the transgastricshort-axis view. At this level, direct measurement of thesegment length is possible, the papillary muscles servingas internal landmark to divide the ventricle into anteriorand posterior segments. While in the first few days aftera transmural infarction, ventricular dilatation mostlyinvolves the infarcted segment, remodeling of the entireleft ventricular cavity involving adjacent and nonischemicregions will be observed later.F. Left Ventricular AneurysmA left ventricular aneurysm is a common complicationamong survivors of nonreperfused transmural myocardialinfarction. Aneurysms occur four times more often at theapex and at the anterior wall than at the inferobasal wall(Fig. 8.25). True aneurysm results from expansion of theinfarcted area and thinning of the myocardium. All threelayers of the ventricular wall are preserved. Echocardiographically,the aneurysmal segments are dyskinetic or akinetic,and the distortion of the left ventricular shape consists of anoutpouching of ventricular myocardium with well definedborders (Figs. 8.26 and 8.27). A wide neck persists indiastole. However, differentiating a true aneurysm from apseudoaneurysm may sometimes be difficult.A pseudoaneurysm, or false aneurysm, is a relativelyrare complication of myocardial infarction. It is theresult of a perforation of the ventricular free wall resultingin a localized hemopericardium which is contained by theparietal pericardium (Fig. 8.28). Echocardiographically,there is a pouchlike configuration of the LV with anabrupt discontinuity of myocardial echoes at the neck ofthe false aneurysm which is typically narrow. Pseudoaneurysmsare commonly filled with thrombus but flowto and from the pseudoaneurysm may be documented byDoppler. Bulging also can be observed in the false aneurysmduring systole. As a ventricular pseudoaneurysm is acontained rupture, mortality is high and immediate surgeryis warranted as soon as the diagnosis is made. Figure 8.29summarizes the difference between a pseudo and a trueaneurysm.