The association between aortic regurgitation and undetermined embolic infarction with aortic complex plaque

Background: Retrograde embolism from the descending thoracic aorta is one possible cause of undetermined ischemic stroke. Significant aortic regurgitation can increase the amount of reversed flow in the thoracic aorta and thus is associated with an increased incidence of stroke. Aims: This study aimed to examine the association between significant aortic regurgitation and undetermined embolic infarction with aortic complex plaques. Methods: This study included 380 patients with undetermined embolic stroke who did not have abnormal flow such as atrial septal defect, patent foramen ovale determined by agitated saline bubble test, intracardiac thrombi on transesophageal echocardiography, atrial fibrillation, or small vessel stroke, cerebral artery, and carotid stenosis on the brain magnetic resonance imaging. The patients were divided into the complex aortic plaques group (n = 63), which was defined as having plaque with >4 mm in thickness, ulceration, or high mobility, and the no complex aortic plaques group (n = 317). Results: Transesophageal echocardiography with a bubble study, brain MRI, and laboratory tests were performed for all subjects. Significant aortic regurgitation was more prevalent in patients with undetermined embolic stroke and complex aortic plaques than in patients without complex aortic plaques (adjusted OR = 4.981; 95% CI = 1.323–18.876, P = 0.028). In addition, the distribution of complex aortic plaques according to the severity of aortic regurgitation in patients with undetermined embolic stroke had a tendency toward the ascending thoracic aorta and proximal aortic arch. Conclusions: Significant aortic regurgitation may affect undetermined embolic stroke in patients with complex aortic plaques.