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Background and Purpose— We aim to determine the potential impact on stroke thrombolysis of drip-and-ship helicopter flights and specifically of their low-frequency vibrations (LFVs). Methods— Mice with a middle cerebral artery autologous thromboembolic occlusion were randomized to receive rtPA (recombinant tissue-type plasminogen activator; or saline) 90 minutes later in 3 different settings: (1) a motion platform simulator that reproduced the LFV signature of the helicopter, (2) a standardized actual helicopter flight, and (3) a ground control. Results— Mice assigned to the LFV simulation while receiving tPA had smaller infarctions (31.6 versus 54.9 mm 3 ; P =0.007) and increased favorable neurological outcomes (86% versus 28%; P =0.0001) when compared with ground controls. Surprisingly, mice receiving tPA in the helicopter did not exhibit smaller infarctions (47.8 versus 54.9 mm 3 ; P =0.58) nor improved neurological outcomes (37% versus 28%; P =0.71). This could be due to a causative effect of the 20- to 30-Hz band, which was inadvertently attenuated during actual flights. Mice using saline showed no differences between the LFV simulator and controls with respect to infarct size (80.9 versus 95.3; P =0.81) or neurological outcomes (25% versus 11%; P =0.24), ruling out an effect of LFV alone. There were no differences in blood-brain barrier permeability between LFV simulator or helicopter, compared with controls (2.45–3.02 versus 4.82 mm 3 ; P =0.14). Conclusions— Vibration in the low-frequency range (0.5–120 Hz) is synergistic with rtPA, significantly improving the effectiveness of thrombolysis without impairing blood-brain barrier permeability. Our findings reveal LFV as a novel, safe, and simple-to-deliver intervention that could improve the outcomes of patients. Visual Overview— An online visual overview is available for this article.

Background: Understanding the potential effects on stroke outcome of the unique physical factors present in a helicopter ambulance flight is critical in the era of thrombectomy. However, this factor in patient care has not been adequately investigated. Methods: This was a prospective randomized blinded end-point animal study. A murine model of middle cerebral artery autologous thromboembolic occlusion (eMCAO) with rtPA reperfusion was exposed to three different settings: 1) a standardized actual helicopter flight, 2) a motion platform simulator that delivered the exact LFV signature of the helicopter, and 3) a ground control. Outcome measures included infarct size and BBB permeability on MRI, and neurological scores. Results: A total of 106 mice were analyzed. Within the rtPA group, LFV simulator mice displayed lower infarction volumes on MRI (31.6 vs. 54.9 mm 3 , p=0.007) and improved neurological scores (87 vs. 28%, p=0.0001) compared to ground control mice. By contrast, mice receiving saline did not show change in either infarction volume (80.9 vs. 95.3, p=0.8) or neurological scores (37 vs. 28%, p=0.7). No differences were seen in the actual helicopter flight group as compared with ground control. No treatment group showed any difference in permeability of the blood brain barrier, assessed by MRI. Conclusion: We found a synergistic beneficial effect of combining helicopter-like LFV and rtPA, which could provide a novel, safe, and potentially more efficacious intervention for patients with stroke. These results also suggest that non-LFV helicopter physical factors, such, as hypobaric environment, accelerations and noise, may have a negating effect on the otherwise positive effect of helicopter vibration on stroke outcomes. If so, strategies to minimize these negating factors might be expected to improve patient outcome.

Background: There are limited data on the baseline characteristics and clinical outcomes of patients who have recurrent hemispheric syndromes in the territory of symptomatic atherosclerotic internal carotid artery occlusion (AICAO). Methods: Baseline characteristics and clinical outcomes were compared between patients with (rHEM+) and without (rHEM-) recurrent ipsilateral hemispheric syndromes at the time of randomization into the Carotid Occlusion Surgery Study (COSS) based on local investigator clinical impression. Results: Of 195 participants who were randomized, 100 (51%) were rHEM+ (50 in each study arm) and 95 were rHEM-(48 nonsurgical, 47 surgical). Baseline characteristics between rHEM+ and rHEM- participants were similar except that rHEM+ participants were more likely to have had a previous stroke prior to entry event (59% vs 22%, p < 0.001) and to have had TIA vs stroke as the entry event (61% vs 20%, p 0.10). For the nonsurgical participants, there was no statistically significant difference in the primary endpoint for those rHEM+ vs rHEM- (26.3% vs 18.9%, p=.410) Conclusion: Patients with recurrent hemispheric stroke syndromes enrolled in the COSS trial were more likely to have had previous stroke and to have TIAs as the entry event to randomization. Given the lack of surgical treatment benefit seen in these patients, early aggressive risk factor measures should be prioritized to reduce recurrent strokes, including blood pressure control which was associated with a 70% reduction in stroke in the nonsurgical group in COSS ( Neurology 2014; 82:1027-1032).

Background and Purpose We aimed to prospectively determine whether the incidence of obstructive sleep apnea in patients with recent stroke was significantly different from that of a sex- and age-matched control group with no major medical problems. Methods We prospectively performed overnight polysomnography in 24 patients with a recent stroke (13 men and 11 women; mean age [±SD], 64.6±10.4 years) and 27 subjects without stroke (13 men and 14 women; mean age, 61.6±8.8 years). Patients with either ischemic or hemorrhagic stroke were entered into this study. Polysomnographic evaluations were performed within approximately 2 to 5 weeks after each patient’s stroke. Results Obstructive sleep apnea was found in 10 of 13 men with stroke (77%) and in only 3 of 13 male subjects without stroke (23%) ( P =.0169). Seven of 11 women with stroke (64%) had obstructive sleep apnea, while only 2 of 14 female subjects without stroke (14%) had obstructive sleep apnea ( P =.0168). For men with stroke, the mean apnea/hypopnea index (±SE) was 21.5±4.2 events per hour, while for male subjects without stroke it was 4.8±1.8 events per hour ( P =.0014). For women with stroke the mean apnea/hypopnea index was 31.6±8.8 events per hour, while for female subjects without stroke it was 2.9±1.6 events per hour ( P =.0024). The 4-year mortality for patients with stroke was 20.8%. All patients with stroke who died had obstructive sleep apnea. Conclusions Patients with stroke have an increased incidence of obstructive sleep apnea compared with normal sex- and age-matched control subjects. Hypoxia and hemodynamic responses to obstructive sleep apnea may have predisposed these patients to stroke.