[A Study of Etiology Classification of Minor Stroke Based on TOAST and ASCO Systems].

Objectives: To investigate the differences in the etiology between minor stroke and non-minor stroke based on TOAST and ASCO systems, and to guide the early intervention for minor stroke.

Methods: We retrospectively analyzed the patients with acute ischemic stroke admitted to our department from July 2012 to July 2014. We sub-typed minor stroke patients and non-minor stroke patients in etiology using Trial of Org 10172 in Acute Stroke Treatment (TOAST) and ASCO (A for atherosclerosis, S for small vessel disease, C for Cardiac source, O for other cause) systems respectively to investigate the difference of etiology between the two groups.

Results: We included a total of 406 patients with minor stroke and 651 patients with non-minor stroke. The constituent ratio of TOAST was different (<0.001) between the two groups. small-artery occlusion (SAO) was the highest cause (40.4%, 164 cases) in minor stroke group, while stroke undertermined etiology (SUE) was the most common (30.9%, 201 cases)in non-minor stroke group. The A1+2 ratio and C1+2 ratio in minor stroke group were lower than those in non-minor stroke group (22.8% vs. 35.4%, <0.001; 19.3% vs. 32.1%, <0.001), and the ratio of S1+2 was higher than that in non-minor stroke group (49.8% vs. 27.3%, <0.001).

Conclusions: The etiology of minor stroke is different to non-minor stroke SAO is the most common cause in minor stroke, while CE and LAA are more common in non-minor stroke.