Stroke Alert: A Review of Current Clinical Stroke Literature
By Matthew E. Fink, MD, Professor and Chairman, Department of Neurology, Weill Cornell Medical College, and Neurologist-in-Chief, New York Presbyterian Hospital
Recanalization of Basilar Artery Occlusion May Be Beneficial Up to 48 Hours After Onset of Symptoms
Source: Strbian D, et al. Thrombolysis of basilar artery occlusion: Impact of baseline ischemia and time. Ann Neurol 2013;73:688-694.
It is unclear how long one can wait before attempt-ing intra-arterial interventions in patients with basilar artery occlusion. Neurologists at Helsinki University, Finland, prospectively evaluated 184 consecutive patients with angiographically proven basilar artery occlusion. The majority of these patients received intravenous alteplase and concomitant heparin before the intervention. Baseline ischemia was defined as an Acute Stroke Prognosis Early CT Score (ASPECTS) < 8. Onset of symptoms to treatment time was evaluated as a variable from 0 hours to 48 hours. Successful recanalization was defined as attaining a TIMI score of 2 to 3. Poor 3-month outcome was evaluated and defined as a modified Rankin score of 3 to 6.
Ninety-six percent of the patients with baseline
ASPECTS score < 8 had a poor 3-month outcome, and a similar number, 94%, was observed in those with confirmed recanalization. In contrast, half of the patients with ASPECTS score > 8 and successful recanalization achieved a good outcome. Of note, onset of symptoms to treatment time, as a variable, was not associated with poor outcome in any of the analyses. The factors independently associated with poor outcome were older age, high baseline NIH Stroke Scale, lack of recanalization, history of atrial fibrillation, and asymptomatic intracerebral hemorrhage.
Based on this single-center prospective study, it appears that in the absence of extensive baseline ischemia, recanalization of basilar artery occlusion can be beneficial up to 48 hours after onset of symptoms with good outcomes demonstrated in 50% of patients.
Non-Dominant Hemisphere Ischemic Stroke May Impair Affective Empathy
Source: Leigh R, et al. Acute lesions that impair affective empathy. Brain 2013;136:2539-2549.
Empathy, defined as the ability to make inferences about what other people think and feel, is an elusive quality that is rarely assessed in patients who present with acute stroke. Several important neurological disorders are known to disrupt various aspects of empathy, including autism, frontotemporal dementia, traumatic head injury, and schizophrenia. In functional imaging studies using functional MRI of healthy participants, as well as previous lesion studies, a distinct neural network has been defined that plays a role in empathy — the prefrontal cortex, orbitofrontal gyrus, anterior insula, anterior cingulate cortex, temporal pole, amygdala, and the temporal parietal junction. The authors of this study hypothesized that right-sided lesions to the brain would cause impaired affective empathy, and they studied 27 patients with acute right hemisphere ischemic strokes and 24 neurologically intact patients on a test of affective empathy.
Acute impairment of affective empathy was identified in patients who had infarcts in the hypothesized network as noted above, particularly in lesions that involve the left anterior temporal pole and the anterior insula. Patients who had impaired empathy also had impaired comprehension of affective prosody, and had difficulty in understanding the affective nature of speech when they communicated with others. Patients with impaired empathy did not show any difference in performance on tests of hemispatial neglect, the volume of infarcts, or sex distribution, compared to controls. Impaired empathy is a subtle manifestation of non-dominant hemisphere ischemic stroke, and should be evaluated and assessed as part of a comprehensive neurocognitive battery for patients who have had ischemic stroke.
