A new stroke mimic prediction scale in a stroke center with a high thrombolysis rate

Patients reaching the emergency department (ED) with symptoms of acute ischemic stroke (AIS) may be affected by a stroke mimics (SMs). A prompt clinical diagnosis could avoid unnecessary thrombolysis. We evaluated a new and rapid approach, the Santa Maria Nuova-Stroke Mimic (SMN-SM) scale, to improve a prompt clinical diagnosis. 340 consecutive patients admitted to the ED with suspected AIS were evaluated. The final diagnosis was: AIS in 267 (78,5%) and SMs in 73 (21,5%) patients. Multivariate logistical analysis showed that the following features – lack of facial paralysis, dizziness, migraine, seizure disorders, blood pressure <150, cognitive impairment, and female sex – were significantly more abundant in patients with SMs than in AIS. To each of these features we assigned a numerical score and we performed a receiver operating characteristic analysis. When the score of the scale was above 8 (cut-point), we obtained a specificity of 93% and a sensitivity of 56% for a SM diagnosis. Thus, the SMN-SM scale seems a rather useful tool to improve SMs diagnosis.