MULTIPLANE TRANSESOPHAGEAL ECHOCARDIOGRAPHY AND STROKE

Transesophageal echocardiography (TEE) is considered a basic tool in t he diagnostic and follow-up evaluation of stroke patients, since vp to 40% of cerebral ischemic events are presumed to have a cardiac origin . TEE offers a superior resolution of the posterior cardiac structures , such as left atrium and appendage and atrial septum, as well as of t he aorta. By means of TEE, evidence has accumulated that some cardiova scular abnormalities (left-sided thrombi, tumors and vegetative lesion s, complicated plaques of the aortic arch) are associated with ischemi c stroke. Nevertheless, some issues remain unresolved. Will exclusion of atrial thrombus by multiplane TEE preclude embolism after cardiover sion of atrial fibrillation? If anticoagulation before and after cardi oversion is needed to provide adequate protection against embolism, wi ll TEE be indicated in all patients? Moreover, can the detection of sp ontaneous echo contrast or enlarged and hypokinetic left atrial append age in atrial fibrillation modify the therapeutic strategy? Is atrial septal aneurysm (ASA) a real embolic source, particularly when a right -to-left shunt is not associated? Considering the high prevalence of p atent foramen ovale (PFO) in normal subjects, how can we identify pati ents at higher risk of embolism? Furthermore, methodologic points have to be taken into account when we analyze data from the literature. Fi rst, most studies are retrospective; a sole prospective study demonstr ated that atherosclerotic plaques >4 mm thick in the aortic arch are s ignificant predictors of recurrent brain infarction and other cardiova scular events in patients greater than or equal to 60 years of age. Se cond, the association between the aforementioned cardiac abnormalities (mainly ASA and PFO) and cardiogenic embolism is biased by the patien t-enrollment criteria used in those studies so that their pathogenetic role has not yet been established. prospective studies with the enrol lment of appropriate control groups will be necessary to define what c an be considered a marker of embolic risk; the diagnosis ''cardiogenic embolism'' will not be a definitive diagnosis in most cases. (C) 1998 by Excerpta Medica, Inc.