Atrial Cardiopathy and Stroke Prevention.

Abstract

Many patients with ischemic stroke have a stroke syndrome and neuroimaging findings consistent with embolism, but no evidence of atrial fibrillation. Recent data suggest that the pathological atrial substrate, or atrial cardiopathy, that underlies atrial fibrillation, rather than atrial fibrillation itself, may be an important cause of unexplained strokes. This paper will review the literature on the rationale and data behind the concept of atrial cardiopathy, its pathophysiology, suggested biomarkers of atrial cardiopathy, and therapeutic implications. Several lines of evidence suggest that patients can have strokes associated with disorders of the atrium, even without frank atrial fibrillation. Even in patients with paroxysmal atrial fibrillation, cardiac emboli may occur temporally disassociated from episodes of atrial fibrillation, and the left atrial appendage flow patterns associated with increased thromboembolic risk may occur even when the surface electrocardiogram demonstrates normal sinus rhythm. Biomarkers of left atrial structural and electrophysiological abnormalities have been associated with stroke risk, even in the absence of atrial fibrillation. Atrial cardiopathy, as determined by the presence of biomarkers of left atrial dysfunction, may provide a therapeutic target to reduce the risk of cardioembolic stroke in the absence of atrial fibrillation. Clinical trials are currently ongoing to test this hypothesis.