High Middle Cerebral Artery Pulsatility Index Predicts An Unfavorable Outcome And Correlates With Heart Functions In Acute Ischemic Stroke Without Vessel Stenosis

Background and Purpose: To determine the parameters of transcranial color-coded duplex sonography (TCCS) related to unfavorable outcomes, and further to clarify the correlation between those parameters and heart functions in acute ischemic stroke without vessel stenosis. Methods: Patients were selected from a comprehensive stroke center between October 2012 and June 2019. Inclusion criteria were: acute ischemic stroke or TIA; able to measure blood flow of either the left or right middle cerebral artery (M1) by TCCS with ≤7 days from onset; and have no vessel stenoses or occlusions assessed by MRA and carotid artery ultrasonography. An unfavorable outcome was defined as mRS score of 2 to 6 at 3 months from the onset. First, we investigated the parameters of TCCS related to unfavorable outcomes (cohort A). Second, the correlation between those parameters and heart functions assessed by transthoracic echocardiography was evaluated (cohort B). Results: We screened 1,529 consecutive ischemic stroke patients, including 173 in cohort A (146 (84%) male, median age 59 years) and 192 in cohort B (162 (84%) male, median age 60 years) (Figure A). In cohort A, high M1 pulsatility index (PI) (OR 0.043; 95% CI 0.005-0.407; p = 0.006) was independently associated with an unfavorable outcome (Figure B). In cohort B, higher age (OR 1.532; 95% CI 1.118-2.009; p = 0.008), higher E/e' (OR 1.143; 95% CI 1.011-1.292; p = 0.033), and aortic valve regurgitation (AR > mild) (OR 4.780; 95% CI 1.261-18.114; p = 0.021) were factors independently associated with high M1 PI (Figure C). Conclusions: High M1 PI predicts an unfavorable outcome and correlates with high E/e' suggesting diastolic heart dysfunction and aortic valve regurgitation in acute ischemic stroke without vessel lesion.