Editors' note: Carotid plaques and detection of atrial fibrillation in embolic stroke of undetermined source

In “Carotid plaques and detection of atrial fibrillation in embolic stroke of undetermined source,” Ntaios et al. studied 777 patients with embolic stroke of undetermined source (ESUS) and found that the presence of ipsilateral nonstenotic carotid plaque was associated with a significantly lower likelihood for atrial fibrillation. Siegler et al. questioned the modality used to identify nonstenotic carotid plaque and paroxysmal atrial fibrillation, given that this affects incidence rates. Furthermore, they noted that although the authors commented on the frequency of conditions during which atrial fibrillation was detected (such as routine ECG, stroke recurrence, and myocardial infarction), it would have been useful to compare the incidence rates for patients with and without plaque. Ntaios responded that unfortunately, they did not have access to information about the technique used to diagnose carotid plaque or atrial fibrillation and that they did not think it was appropriate to compare the incidence of conditions during which atrial fibrillation was detected without this information. Lattanzi et al. commented that it would be useful to assess the relationship between plaques and atrial fibrillation and other variables, such as atrial cardiopathy, which has been shown to be inversely related to artery-to-artery strokes. Ntaios responded that they have performed additional analysis and hope to have their results published soon. It is clear that further research into workup and management of ESUS is needed. In “Carotid plaques and detection of atrial fibrillation in embolic stroke of undetermined source,” Ntaios et al. studied 777 patients with embolic stroke of undetermined source (ESUS) and found that the presence of ipsilateral nonstenotic carotid plaque was associated with a significantly lower likelihood for atrial fibrillation. Siegler et al. questioned the modality used to identify nonstenotic carotid plaque and paroxysmal atrial fibrillation, given that this affects incidence rates. Furthermore, they noted that although the authors commented on the frequency of conditions during which atrial fibrillation was detected (such as routine ECG, stroke recurrence, and myocardial infarction), it would have been useful to compare the incidence rates for patients with and without plaque. Ntaios responded that unfortunately, they did not have access to information about the technique used to diagnose carotid plaque or atrial fibrillation and that they did not think it was appropriate to compare the incidence of conditions during which atrial fibrillation was detected without this information. Lattanzi et al. commented that it would be useful to assess the relationship between plaques and atrial fibrillation and other variables, such as atrial cardiopathy, which has been shown to be inversely related to artery-to-artery strokes. Ntaios responded that they have performed additional analysis and hope to have their results published soon. It is clear that further research into workup and management of ESUS is needed.