Recurrent stroke in patients with right-to-left shunt and cryptogenic stroke

Abstract

Objective To investigate the relationship between the right-to-left shunt (RLS) detected with contrast-enhanced transcranial Doppler (c-TCD) and recurrent stroke in patients with cryptogenic stroke. Methods The consecutive patients with ischemic stroke were enrolled. The patients with cryptogenic stroke were screened according to the TOAST criteria. They were divided into either a RLS positive group or a RLS negative group according to the c-TCD findings, and then they were followed up for a period of one year. They were also divided into a recurrent group and a non-recurrent group according to whether they had recurrence or not. Results A total of 118 patients with cryptogenic ischemic stroke were enrolled, including 46 in the RLS positive group, 72 in the RLS negative group, 10 in the recurrent group, and 108 in the non-recurrent group. There were no significant differences in demographic and baseline data between the RLS negative group and the RLS positive group. There were significant differences in RLS positive rate (7/10 vs. 39/108; P=0.046) and proportion of patients with server RLS (2/10 vs. 1/108; P=0.019) between the recurrent group and the non-recurrent group. Multivariate logistic regression analysis showed that the positive RLS was an independent predictor of recurrent stroke (odds ratio 4.896, 95% confidence interval 1.135-21.120; P=0.033). Conclusions The positive RLS may be an independent risk factor for the recurrence in patients with cryptogenic ischemic stroke. Key words: Stroke; Brain Ischemia; Intracranial Embolism; Heart Septal Defects, Atrial; Ultrasonography, Doppler, Transcranial; Recurrence