ABC | Volume 113, Nº1, July 2019

Statement Position Statement on Indications of Echocardiography in Adults – 2019 Arq Bras Cardiol. 2019; 113(1):135-181 stroke include large artery atherosclerosis, small vessel occlusion (lacunar), and other etiologies. 205 In patients who are at risk or who have already had embolic neurologic events, the main role of echocardiography is to identify the presence of an emboligenic source, to determine the probability of such a source being a possible cause of ischemic stroke or systemic embolism and to guide the therapy of these patients. We can classify cardiac diseases as for their emboligenic potential under high and low risk conditions (Table 39). The main causes of ischemic stroke of cardioembolic origin are: atrial fibrillation, associated or not with rheumatic MS (five-fold risk of stroke); left ventricular dysfunction (two to three times greater risk of ischemic stroke than the general population); 206 acute myocardial infarction (the risk is possibly decreasing by the implementation of early reperfusion therapies); 207 mechanical valvular prostheses (annual risk of ischemic stroke at 4.0%); 208 and infectious endocarditis (one in five cases are complicated by ischemic stroke). 209 Variable rates of annual recurrence of ischemic stroke have been reported in patients with aortic arch atheroma (less than 3 to 12%). 210 The patent foramen ovale (PFO) can serve as a passageway from a paradoxical embolism of the venous to the arterial circulation. Although patients with an ischemic stroke of indeterminate (cryptogenic) etiology have a higher incidence of FOP than those with known ischemic stroke cause, 211 a large study reported that the presence of a PFO was not associated with an increased risk of recurrence of ischemic stroke. 212 Other more rare causes of embolism include papillary fibroelastoma, myxoma, and mitral calcification. The cardioembolic etiology of ischemic stroke should be suspected in the presence of severe onset of early neurologic deficit without prodromes, multiple brain lesions in multiple vascular territories, and recurrent ischemic stroke in a short period of time. 213 Systemic embolization to other organs such as spleen and kidneys at the time of the ischemic stroke increases the suspicion of cardioembolic etiology. 213 TTE and/or TEE should be recommended in patients with suspected cardiac embolic source, including ischemic stroke and transient ischemic attack (TIA) or systemic embolism. TTE is more suitable for evaluation of embolic sources present in previous cardiac structures, such as the apical thrombus investigation of the left ventricle. In contrast, during the TEE, the transducer is positioned in the esophagus, and the probe is closer to the posterior heart structures. The esophagus is also adjacent to the LA, so TEE corresponds to the gold standard examination for thrombus screening in the left atrial appendix, with sensitivity and specificity approaching 99%. TEE should be recommended as an initial diagnostic tool in the assessment of cardiac embolic source in patients with ischemic stroke, especially in those where the therapeutic decision (anticoagulation or cardioversion) will depend on the echocardiographic findings. TEE should also be recommended when TTE imaging is of poor quality in young patients with ischemic stroke, in patients with ischemic stroke of undetermined etiology, and in those with non-lacunar ischemic stroke. TTE may not be useful when TEE is already programmed for TEE, such as in the evaluation of intracardiac masses, prosthetic heart valves, the thoracic aorta, or to guide percutaneous procedures. TEE should not be recommended when TTE findings are compatible with the embolic cardiac source. Both TTE and TEE should not be recommended in patients whose results will not guide the therapeutic decision. Table 40 lists the main recommendations of TTE and/or TEE in patients with TIA, ischemic stroke or systemic embolism. Table 38 – Recommendations for the use of echocardiographic contrast agents in chronic coronary disease Recommendation Class of recommendation Level of evidence Improvement of endocardial border delineation and analysis of global or regional ventricular function when endocardial visibility in two or more segments is limited I B Myocardial perfusion analysis in the diagnosis of chronic coronary disease, both in the assessment of ischemia and viability as an adjunct to the modalities of stress echocardiography IIa B Assessment of the coronary flow reserve in the study of the functional repercussion of already known or viable coronary lesions IIa B Use in the presence or suspected of significant intracardiac shunts III B Routine use of contrast in patients whose image and endocardial edge delineation of the left ventricle are of adequate quality III C Table 39 – Classification of cardiac diseases regarding their emboligenic potential High risk Low risk Intracavitary thrombus Patent foramen ovale Atrial fibrillation Interatrial septum aneurysm Acute myocardial infarctation Interatrial communication Dilated cardiomyopathies Spontaneous contrast Infectious endocarditis Lambl excrescences Valve prostheses Mitral valvular calcification Rheumatic mitral stenosis Aortic valve calcification Left atrial myxoma Endocarditis marantica Papillary fibroelastoma Mitral valve prolapse Ulcerated plaques in the aorta 165