***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    ***EXAMPLES*** 
    Input: Background — Thrombolytic therapy with intravenous alteplase within 4.5 hours of ischemic stroke onset increases the overall likelihood of an excellent outcome ( no , or nondisabling , symptoms ) . Any improvement in functional outcome distribution has value , and herein we provide an assessment of the effect of alteplase on the distribution of the functional level by treatment delay , age , and stroke severity . Methods — Prespecified pooled analysis of 6756 patients from 9 r and omized trials comparing alteplase versus placebo/open control . Ordinal logistic regression models assessed treatment differences after adjustment for treatment delay , age , stroke severity , and relevant interaction term(s ) . Results — Treatment with alteplase was beneficial for a delay in treatment extending to 4.5 hours after stroke onset , with a greater benefit with earlier treatment . Neither age nor stroke severity significantly influenced the slope of the relationship between benefit and time to treatment initiation . For the observed case mix of patients treated within 4.5 hours of stroke onset ( mean 3 hours and 20 minutes ) , the net absolute benefit from alteplase ( ie , the difference between those who would do better if given alteplase and those who would do worse ) was 55 patients per 1000 treated ( 95 % confidence interval , 13–91 ; P=0.004 ) . Conclusions — Treatment with intravenous alteplase initiated within 4.5 hours of stroke onset increases the chance of achieving an improved level of function for all patients across the age spectrum , including the over 80s and across all severities of stroke studied ( top versus bottom fifth means : 22 versus 4 ) ; the earlier that treatment is initiated , the greater the benefit Background Limited efficacy of IV recombinant tissue plasminogen activator ( rt-PA ) for large vessel occlusions ( LVO ) raises doubts about its utility prior to endovascular therapy . Purpose To compare outcomes and hospital costs for anterior circulation LVOs ( middle cerebral artery , internal carotid artery terminus ( ICA-T ) ) treated with either primary endovascular therapy alone ( EV-Only ) or bridging therapy ( IV+EV ) ) . Methods A single-center retrospective analysis was performed . Clinical and demographic data were collected prospect ively and relevant cost data were obtained for each patient in the study . Results 90 consecutive patients were divided into EV-Only ( n=52 ) and IV+EV ( n=38 ) groups . There was no difference in demographics , stroke severity , or clot distribution . The mean ( SD ) time to presentation was 5:19 ( 4:30 ) hours in the EV-Only group and 1:46 ( 0:52 ) hours in the IV+EV group ( p<0.0001 ) . Recanalization : EV-Only 35 ( 67 % ) versus IV+EV 31 ( 81.6 % ) ( p=0.12 ) . Favorable outcome : EV-Only 26 ( 50 % ) versus IV+EV 22 ( 58 % ) ( p=0.45 ) . For patients presenting within 4.5 hours ( n=64 ) : Recanalization : EV-Only 21/26 ( 81 % ) versus IV+EV 31/38 ( 81.6 % ) ( p=0.93 ) . Favorable outcome : EV-Only 14/26 ( 54 % ) versus IV+EV 22/38 ( 58 % ) ( p=0.75 ) . There was no significant difference in rates of hemorrhage , mortality , home discharge , or length of stay . A stent retriever was used in 67 cases ( 74.4 % ) , with similar recanalization , outcomes , and number of passes in the EV-Only and IV+EV groups . The mean ( SD ) total hospital cost was $ 33 810 ( 13 505 ) for the EV-Only group and $ 40 743 ( 17 177 ) for the IV+EV group ( p=0.02 ) . The direct cost was $ 23 034 ( 8786 ) for the EV-Only group and $ 28 711 ( 11 406 ) for the IV+EV group ( p=0.007 ) . These significantly higher costs persisted for the subgroup presenting in < 4.5 hours and the stent retriever subgroup . IV rt-PA administration independently predicted higher hospital costs . Conclusions IV rt-PA did not improve recanalization , thrombectomy efficacy , functional outcomes , or length of stay . Combined therapy was associated with significantly higher total and direct hospital costs than endovascular therapy alone Importance Intravenous thrombolysis ( IVT ) followed by mechanical thrombectomy ( MT ) is recommended to treat acute ischemic stroke ( AIS ) with a large vessel occlusion ( LVO ) . Most hospitals do not have on-site MT facilities , and most patients need to be transferred secondarily after IVT ( drip and ship ) , which may have an effect on the neurologic outcome . Objective To compare the functional independence at 3 months between patients treated under the drip- and -ship paradigm and those treated on site ( mothership ) . Design , Setting , and Participants This study used a prospect ively gathered registry of patients with AIS to select patients admitted through the Saint-Antoine and Tenon ( drip and ship ) or the Fondation Rothschild ( mothership ) hospitals from January 1 , 2013 , through April 30 , 2016 . The study included patients older than 18 years treated with bridging therapy for AIS with LVO of the anterior circulation . Among the 159 patients who received MT at the mothership , 100 had been transferred after IVT  from the drip- and -ship hospitals and 59 had received IVT on site . Main Outcomes and Measures The main outcome was 3-month functional independence ( modified Rankin scale score ⩽2 ) . Both groups were compared using a multivariate linear model , including variables that were significantly different in the 2 groups . Results During the study period , 497 patients were hospitalized at the drip- and -ship and mothership hospitals for an AIS eligible to reperfusion therapy ; 11 patients had a basilar artery occlusion and were excluded , leaving 100 patients in the drip- and -ship group ( mean age , 73 years ; age range , 60 - 81 years ; 57 men [ 57.0 % ] ) and 59 in the mothership group ( mean age , 70 years ; age range , 58 - 82 years ; 29 men [ 49.2 % ] ) . The proportion of patients with a favorable neurologic outcome at 3 months was similar in both groups ( drip and ship , 61 [ 61.0 % ] ; mothership , 30 [ 50.8 % ] ; P = .26 ) , even after adjusting the analysis for the baseline National Institutes of Health Stroke Scale score , diffusion-weighted imaging Alberta Stroke Program Early Computed Tomography Score , and general anesthesia ( P = .82 ) . Patients had less severe conditions in the drip- and -ship group ( median baseline National Institutes of Health Stroke Scale score , 15 vs 17 [ P = .03 ] ; median diffusion-weighted imaging Alberta Stroke Program Early Computed Tomography Score , 7.5 vs 7 [ P = .05 ] ) . Process times were longer in the drip- and -ship group ( onset-to-needle time , 150 vs 135 minutes ; onset-to-puncture time , 248 vs 189 minutes ; and onset-to-recanalization time , 297 vs 240 minutes ; P < .001 ) . Both groups were similar in terms of substantial recanalization ( Thrombolysis in Cerebral Ischemia scores 2B to 3 ; drip and ship , 84 [ 84.0 % ] ; mothership , 47 [ 79.7 % ] ; P = .49 ) and symptomatic hemorrhagic transformation ( drip and ship , 2 [ 2.0 % ] ; mothership , 2 [ 3.4 % ] ; P = .63 ) . Conclusions and Relevance This study found that patients treated under the drip- and -ship paradigm also benefit from bridging therapy , with no statistically significant difference compared with those treated directly in a comprehensive stroke center Background Recent studies suggested that preinterventional intravenous ( i. v. ) recombinant tissue plasminogen activator ( rtPA ) as bridging therapy facilitates successful and fast vessel recanalization in endovascular stroke treatment ( EST ) ; however , data on this effect and the associated clinical value are discrepant . Objective This study examined if this discrepancy could be related to an effect-modifying variable , specifically to the exact occlusion site . Methods Retrospective analysis of 239 patients with acute occlusion of the middle cerebral artery ( MCA ) treated with up to date endovascular techniques .  Effects of i. v.-rtPA bridging on clinical outcomes and safety/efficacy of EST , defined as the respective rates of successful , first pass and thrombolysis in cerebral infa rct ion ( TICI ) scale 3 recanalization , were evaluated and stratified according to distal versus proximal occlusion sites . Results Overall , i. v.-rtPA bridging was associated with a significantly higher rate of successful recanalization ( 86.9 % vs. 75.7 % , p = 0.028 ) . i. v.-rtPA bridging-related effects , however , were observable only in distal , but not in proximal MCA-occlusions . In distal occlusions , i. v.-rtPA clearly favored successful recanalization ( adj . OR 4.6 , 95 % -CI 1.5–13.6 , p = 0.006 ) and first-pass successes ( adj . OR 2.8 , 95 % -CI 1.0–7.6 , p = 0.042 ) , but tended to be associated with lower rates of complete ( TICI-3 ) reperfusion ( adj . OR 0.4 , 95 % -CI 0.2–1.1 , p = 0.068 ) . The net effect was a small clinical benefit , reflected in higher rates of strong neurological improvement ( adj . OR : 2.8 , 95 % -CI : 1.1–6.9 , p = 0.03 ) . Conclusion i. v.-rtPA-bridging-related effects are occlusion site-dependent , paralleling similar effects of systemic i. v.-rtPA when applied without subsequent endovascular therapy . In distal occlusions , i. v.-rtPA facilitates thrombectomy , but may also promote distal embolization , with a small clinical benefit as overall net effect . R and omized trials assessing i.v-rtPA bridging need to be stratified according to occlusions sites Background Current guidelines suggest treating blood pressure above 180/105 mm Hg during the first 24 hours in patients with acute ischemic stroke undergoing any form of recanalization therapy . Currently , no studies exist to guide blood pressure management in patients with stroke treated specifically with mechanical thrombectomy .  We aim ed to determine the association between blood pressure parameters within the first 24 hours after mechanical thrombectomy and patient outcomes . Methods and Results We retrospectively studied a consecutive sample of adult patients who underwent mechanical thrombectomy for acute ischemic stroke of the anterior cerebral circulation at 3 institutions from March 2015 to October 2016 . We collected the values of maximum , minimum , and average values of systolic blood pressure , diastolic blood pressure , and mean arterial pressures in the first 24 hours after mechanical thrombectomy . Primary and secondary outcomes were patients ’ functional status at 90 days measured on the modified Rankin scale and the incidence and severity of intracranial hemorrhages within 48 hours . Associations were explored using an ordered multivariable logistic regression analyses . A total of 228 patients were included ( mean age 65.8±14.3 ; 104 males , 45.6 % ) . Maximum systolic blood pressure independently correlated with a worse 90‐day modified Rankin scale and hemorrhagic complications within 48 hours ( adjusted odds ratio=1.02 [ 1.01–1.03 ] , P=0.004 ; 1.02 [ 1.01–1.04 ] , P=0.002 ; respectively ) in multivariable analyses , after adjusting for several possible confounders . Conclusions Higher peak values of systolic blood pressure independently correlated with worse 90‐day modified Rankin scale and a higher rate of hemorrhagic complications . Further prospect i ve studies are warranted to identify whether systolic blood pressure is a therapeutic target to improve outcomes BACKGROUND AND PURPOSE Whether intravenous thrombolysis prior to endovascular treatment in patients with anterior circulation large-vessel occlusion ( LVO ) is indispensable remains unclear . The aim was to retrospectively compare , in a Chinese population , the effectiveness and safety of direct endovascular treatment ( DEVT ) initiated within 4.5 h after onset with bridging therapy in acute anterior circulation LVO stroke patients . METHODS A total of 363 patients , 160 in the bridging therapy group and 203 in the DEVT group , were enrolled between 2014 and 2016 . Using propensity score matching analysis , 276 patients were matched . A modified Rankin Scale score of 0 - 2 was considered as good functional outcome . RESULTS Good functional outcome at 90 days in the DEVT group [ 40.6 % ( 56/138 ) ] did not significantly differ from that in the bridging group [ 44.9 % ( 62/138 ) ] ( P = 
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Conclusion : The findings of our meta- analysis confirmed that bridging strategies improved functional outcomes , successful recanalization rate and reduced mortality rates .
Moreover , the incidence of sICH showed no differences between the bridging strategies and MT alone treatments .