The Relation Between Aortic Arch Branching Types and the Laterality of Cardio-Embolic Stroke

The trajectory of cardiogenic emboli could be affected by anatomical and flow characteristics of the aortic arch. We aimed to study the relation between the different aortic arch patterns and the laterality of cardiogenic emboli.

192 cardioembolic strokes were classified into 3 groups according to the type of the aortic arch; type 1 (n = 69), type 2 (n = 49), type 3 (n = 74). The side and site of the cerebral vessels occlusion were divided into anterior and posterior circulation strokes, and anterior strokes were further subdivided into right or left internal carotid, middle or anterior cerebral arteries occlusion.

Overall, the anterior circulation embolic occlusions were more common than the posterior, and middle cerebral artery more commonly affected than internal carotid artery. The left side propensity was higher either in the total patients' pool or after segregation into atrial fibrillation (AF) and non AF cardio-embolic cases in all types of aortic arch except for type 1 aortic arch in the non AF cases. This propensity tended to get higher with advancement of the aortic arch types but failed to show statistically significant difference between the 3 arch types, however combination of type 2 and 3 arches into a single group showed statistically significant rise in the left side propensity in the total cardioembolic cases (P = 0.039) and in the non AF cardioembolic cases (P = 0.029). The bovine arch also showed increased left side propensity.

Cardioemboli tends to have left anterior cerebrovascular predilection especially with AF. Different geometrical patterns of aortic arch branching seem to affect the laterality of cardioemboli and increase its left side predilection.