Cardiac Workup of Ischemic Stroke

Abstract

Stroke is the leading cause of disability in developed countries and the third cause of mortality. Up to 15-30% of ischemic strokes are caused by cardiac sources of emboli being associated with poor prognosis and high index of fatal recurrence. In order to establish an adequate preventive strategy it is crucial to identify the cause of the embolism. After a complete diagnostic workup up to 30% of strokes remain with an undetermined cause, and most of them are attributed to an embolic mechanism suggesting a cardiac origin.There is no consensus in the extent and optimal approach of cardiac workup of ischemic stroke. Clinical features along with brain imaging and the study of the cerebral vessels with ultrasonography or MRI/CT based angiography can identify other causes or lead to think about a possible cardioembolic origin.Atrial fibrillation is the most common cause of cardioembolic stroke. Identification of occult atrial fibrillation is essential. Baseline ECG, serial ECG(’s), cardiac monitoring during the first 48 hours, and Holter monitoring have detection rates varying from 4 to 8% each separately. Extended cardiac monitoring with event loop recorders has shown higher rates of detection of paroxysmal atrial fibrillation.Cardiac imaging with echocardiography is necessary to identify structural sources of emboli. There is insufficient data to determine which is the optimal approach. Transthoracic echocardiography has an acceptable diagnostic yield in patients with heart disease but transesophageal echocardiography has a higher diagnostic yield and is necessary if no cardiac sources have been identified in patients with cryptogenic stroke with embolic mechanism.

Cardiac MRI Improves Identification of Etiology of Acute Ischemic Stroke

“…Our study compared the findings of CMR with TTE. Although there are no clear guidelines on the optimal imaging modality [32], it is generally believed that TEE is more sensitive than TTE in finding thrombi, especially in the LA appendage and the ascending aorta. It should be noted that all of the patients with an LA appendage thrombus in our study were classified as CAE by RDW due to atrial fibrillation.…”

Clinical and neuroimaging signs of cardioembolic stroke laboratory in children

“…В классификации CASCADE, где первые два признака представлены в качестве критериев диагностики КЭИ, он также не упомина-ется; указывается также, что инфаркт может иметь крупные размеры [11]. Действительно, в силу значи-тельного размера кардиальный эмбол может вызы-вать окклюзию крупной церебральной артерии, что приводит к обширному инфаркту, а при фрагмента-ции эмбола наблюдаются множественные окклю-зии, приводящие к инфарктам в различных артери-альных территориях преимущественно каротидных систем [33][34][35]. Множественные инфаркты в груп-пе КЭИ выявили у 30% обследуемых детей (в иссле-довании М. Ziesmann и соавт.…”

Definitions for Lacunar Syndromes, Lacunar Strokes, Lacunar Infarcts and Lacunes: from Clinical to Neuroimaging

“…: ultrasound imaging and Doppler sonography, transthoracic echocardiography, Holter, etc.) [13] . Lacunar infarcts are small cerebral infarctions (less than 15 mm in diameter) located in the blood supply territory of brain penetrating arterioles (lenticuloestriate, thalamogeniculate, thalamoperforating and paramedian pontine) (Figure 1) caused mainly by microatheromatosis or intracranial atheromatous branch disease, in the absence of emboligen heart disease, severe stenosis of supra-aortic trunks or another unusual etiology (i.e.…”