Atrial fibrillation detection after cryptogenic stroke.

Abstract

Ischemic stroke is a significant cause of mortality and of serious long-term morbidity. It is estimated that cryptogenic stroke (stroke whose underlying causes remain unknown despite a complete work-up,) accounts for about 20–40 % of all ischemic events, one quarter of which tend to be recurrent [1]. Paroxysmal and persistent atrial fibrillation (AF) is a well-recognized cause of ischemic stroke, and the risk may be reduced with anticoagulation. However, only 5 % of patients are diagnosed to have AF after an ischemic stroke. Indeed the use of traditional monitoring techniques may not detect episodes of asymptomatic paroxysmal AF, which might underlie some apparently ‘‘cryptogenic’’ strokes. Therefore, the most effective duration of ECG monitoring has not been determined by current guidelines [2]. Nowadays, external and implanted loop recorders may allow identification of silent AF, thus increasing AF detection rate. However, the effectiveness of prolonged heart rhythm monitoring in patients with cryptogenic stroke is still unproved [3, 4].