***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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    Input: BACKGROUND Bronchoscopic lung-volume reduction with the use of one-way endobronchial valves is a potential treatment for patients with severe emphysema . To date , the benefits have been modest but have been hypothesized to be much larger in patients without interlobar collateral ventilation than in those with collateral ventilation . METHODS We r and omly assigned patients with severe emphysema and a confirmed absence of collateral ventilation to bronchoscopic endobronchial-valve treatment ( EBV group ) or to continued st and ard medical care ( control group ) .  Primary outcomes were changes from baseline to 6 months in forced expiratory volume in 1 second ( FEV1 ) , forced vital capacity ( FVC ) , and 6-minute walk distance . RESULTS Eighty-four patients were recruited , of whom 16 were excluded because they had collateral ventilation ( 13 patients ) or because lobar segments were inaccessible to the endobronchial valves ( 3 patients ) . The remaining 68 patients ( mean [ ±SD ] age , 59±9 years ; 46 were women ) were r and omly assigned to the EBV group ( 34 patients ) or the control group ( 34 ) . At baseline , the FEV1 and FVC were 29±7 % and 77±18 % of the predicted values , respectively , and the 6-minute walk distance was 374±86 m. Intention-to-treat analyses showed significantly greater improvements in the EBV group than in the control group from baseline to 6 months : the increase in FEV1 was greater in the EBV group than in the control group by 140 ml ( 95 % confidence interval [ CI ] , 55 to 225 ) , the increase in FVC was greater by 347 ml ( 95 % CI , 107 to 588 ) , and the increase in the 6-minute walk distance was greater by 74 m ( 95 % CI , 47 to 100 ) ( P<0.01 for all comparisons ) . By 6 months , 23 serious adverse events had been reported in the EBV group , as compared with 5 in the control group ( P<0.001 ) . One patient in the EBV group died . Serious treatment-related adverse events in this group included pneumothorax ( 18 % of patients ) and events requiring valve replacement ( 12 % ) or removal ( 15 % ) . CONCLUSIONS Endobronchial-valve treatment significantly improved pulmonary function and exercise capacity in patients with severe emphysema characterized by an absence of interlobar collateral ventilation . ( Funded by the Netherl and s Organization for Health Research and Development and the University Medical Center Groningen ; Netherl and s Trial Register number , NTR2876 . ) This multicentre , blinded , sham-controlled study was performed to assess the safety and effectiveness of bronchial valve therapy using a bilateral upper lobe treatment approach without the goal of lobar atelectasis . Patients with upper lobe predominant severe emphysema were r and omised to bronchoscopy with ( n=37 ) or without ( n=36 ) IBV Valves  for a 3-month blinded phase . A positive responder was defined as having both a ≥4-point improvement in St George ’s Respiratory Question naire ( SGRQ ) and a lobar volume shift as measured by quantitative computed tomography . At 3 months , there were eight ( 24 % ) positive responders in the treated group versus none ( 0 % ) in the control group ( p=0.002 ) . Also , there was a significant shift in volume in the treated group from the upper lobes ( mean±sd -7.3±9.0 % ) to the non-treated lobes ( 6.7±14.5 % ) , with minimal change in the control group ( p<0.05 ) . Mean SGRQ total score improved in both groups ( treatment : -4.3±16.2 ; control : -3.6±10.7 ) . The procedure and devices were well tolerated and there were no differences in adverse events reported in the treatment and control groups . Treatment with bronchial valves without complete lobar occlusion in both upper lobes was safe , but not effective in the majority of patients Background There is a clinical need for therapeutic options to reduce hyperinflation associated with severe emphysema . Endobronchial Coils ( coils ) are nitinol devices implanted bronchoscopically under fluoroscopic guidance to re-tension the lung . We report the medium term effectiveness and safety of coils in a study of patients with emphysema . Methods Forty five subjects with severe airflow obstruction and hyperinflation received bilateral sequential treatment with coils ( 30 day interval between treatments ) as part of a r and omised controlled trial with a primary endpoint 90 days after the final treatment ( Clinical trials.gov NCT01334307 ) . Further assessment s were made at 180 and 360 days and in this study the primary outcome was the effect of coil treatment on the St. George ’s Respiratory Question naire ( SGRQ ) 360 days following treatment . Results At 360 days following treatment , there was an improvement in the SGRQ score of -6.1±14.0 points ( p = 0.01 ) compared to baseline . Improvements in secondary outcomes were seen with increases in forced expiratory volume in the first second of 8.9 ±22.2 % ( p = 0.002 ) and 6-minute walking distance of 34.1±52.4 m ( p = 0.003 ) . The safety profile was acceptable out to 360 days post-treatment . Conclusions Statistically and clinical ly meaningful benefits in quality of life , exercise capacity and pulmonary function in patients treated with coils are sustained twelve months after treatment . Trial registration information Clinical trials.gov NCT01334307 Introduction Endoscopic lung volume reduction has been developed as a therapeutic option for advanced emphysema . Six-month results following treatment with endoscopic thermal vapor ablation ( InterVapor ™ ; Uptake Medical , Tustin , CA ) were described previously , and here we report observations from the 12-month assessment . Methods Two multicenter , international , single-arm trials of InterVapor ( unilateral upper lobe treatment ) in patients with upper lobe predominant emphysema were conducted . Inclusion criteria : forced expiratory volume in 1 second ( FEV1 ) 15%–45 % predicted , residual volume > 150 % , total lung capacity > 100 % , 6-minute walk distance ( 6MWD ) > 140 m , and diffusing capacity for carbon monoxide > 20 % predicted . Efficacy endpoints : spirometry , body plethysmography , lung volumes by high-resolution computed tomography , St George ’s Respiratory Question naire , modified Medical Research Council dyspnea scale , and 6MWD . All adverse events were collected and independently adjudicated . Results Forty four patients were treated at a mean ( st and ard deviation ) age of 63 ( 5.6 ) years , FEV1 0.86 mL ( 0.25 mL ) ( n = 22 men and 22 women ) . Mean ( st and ard deviation ) changes from baseline at 12 months were : FEV1 86.2 mL ( 173.8 mL ) , St George ’s Respiratory Question naire −11.0 ( 14.0 ) units , treated lobar volume from high-resolution computed tomography −751.8 mL ( 653.9 mL ) , residual volume −302.8 mL ( 775.6 mL ) , 6MWD 18.5 m ( 63.7 m ) , and modified Medical Research Council dyspnea scale score −0.83 ( 0.97 ) ( P < 0.05 for all except 6MWD ) . Improvements were numerically larger at 6 versus 12 months . GOLD stage III and IV patients had similar outcomes at 6 months ; however , improvements relative to baseline were numerically higher in GOLD stage IV patients . Larger improvements were observed in patients with higher heterogeneity . In total , 39 serious adverse events were reported in 23 patients with 10 events in 8 patients between 6 and 12 months . Conclusion Unilateral lobar InterVapor treatment of heterogeneous emphysema improved lung function and health outcomes 1 year following treatment . The magnitude of improvement was larger at 6 months compared to 12 months . Improvements relative to baseline continue to be exhibited at 12 months despite the expected disease related decline over time . Clinical trials NCT 01041586 and NCT Background : In patients with heterogeneous emphysema , surgical and bronchoscopic lung volume reduction ( LVR ) treatments are available . However , for patients with homogeneous emphysema these treatments are hardly investigated and seem less effective . Bronchoscopic LVR coil treatment has been shown to be effective in patients with heterogeneous emphysema , but this treatment has not been exclusively investigated in homogeneous emphysema . Objectives : The aim of this study was to investigate the safety and efficacy of LVR coil treatment in patients with homogeneous emphysema . Methods : In this single-arm , open-label study , patients received a maximum of 12 LVR coils ( PneumRx Inc. , Mountain View , Calif. , USA ) in each upper lobe in two sequential procedures . Tests were performed at baseline and at 6 months . The primary endpoint was the improvement from baseline in 6-min walking distance ( 6MWD ) after treatment . Results : Ten patients with severe airway obstruction and hyperinflation were treated . A median of 11 ( range 10 - 12 ) coils were placed in each lung . Two chronic obstructive pulmonary disease exacerbations and one small pneumothorax were recorded as serious adverse events . At 6 months , 6MWD had improved from 289 to 350 m ( p = 0.005 ) ; forced vital capacity from 2.17 to 2.55 liters ( p = 0.047 ) ; residual volume from 5.04 to 4.44 liters ( p = 0.007 ) and St. George 's Respiratory Question naire from 63 to 48 points ( p = 0.028 ) . Conclusion : LVR coil treatment in homogeneous patients improves hyperinflation , airway resistance , exercise capacity and quality of life with an acceptable safety profile . The benefit of LVR coil treatment is not limited to patients with heterogeneous emphysema , and patients with homogenous emphysema can benefit as well IMPORTANCE Preliminary clinical trials have demonstrated that endobronchial coils compress emphysematous lung tissue and may improve lung function , exercise tolerance , and symptoms in patients with emphysema and severe lung hyperinflation . OBJECTIVE To determine the effectiveness and safety of endobronchial coil treatment . DESIGN , SETTING , AND PARTICIPANTS R and omized clinical trial conducted among 315 patients with emphysema and severe air trapping recruited from 21 North American and 5 European sites from December 2012 through November 2015 . INTERVENTIONS Participants were r and omly assigned to continue usual care alone ( guideline based , including pulmonary rehabilitation and bronchodilators ; n = 157 ) vs usual care plus bilateral coil treatment ( n = 158 ) involving 2 sequential procedures 4 months apart in which 10 to 14 coils were bronchoscopically placed in a single lobe of each lung . MAIN OUTCOMES AND MEASURES The primary effectiveness outcome was difference in absolute change in 6-minute-walk distance between baseline and 12 months ( minimal clinical ly important difference [ MCID ] , 25 m ) . Secondary end points included the difference between groups in 6-minute walk distance responder rate , absolute change in quality of life using the St George 's Respiratory Question naire ( MCID , 4 ) and change in forced expiratory volume in the first second ( FEV1 ; MCID , 10 % ) . The primary safety analysis compared the proportion of participants experiencing at least 1 of 7 prespecified major complications . RESULTS Among 315 participants ( mean age , 64 years ; 52 % women ) , 90 % completed the 12-month follow-up . Median change in 6-minute walk distance at 12 months was 10.3 m with coil treatment vs -7.6 m with usual care , with a between-group difference of 14.6 m ( Hodges-Lehmann 97.5 % CI , 0.4 m to ∞ ; 1-sided P = .02 ) . Improvement of at least 25 m occurred in 40.0 % of patients in the coil group vs 26.9 % with usual care ( odds ratio , 1.8 [ 97.5 % CI , 1.1 to ∞ ] ; unadjusted between-group difference , 11.8 % [ 97.5 % CI , 1.0 % to ∞ ] ; 1-sided P = .01 ) . The between-group difference in median change in FEV1 was 7.0 % ( 97.5 % CI , 3.4 % to ∞ ; 1-sided P < .001 ) , and the between-group St George 's Respiratory Question naire score improved -8.9 points ( 97.5 % CI , -∞ to -6.3 points ; 1-sided P < .001 ) , each favoring the coil group . Major complications ( including pneumonia requiring hospitalization and other potentially life-threatening or fatal events ) occurred in 34.8 % of coil participants vs 19.1 % of usual care ( P = .002 ) . Other serious adverse events including pneumonia ( 20 % coil vs 4.5 % usual care ) and pneumothorax ( 9.7 % vs 0.6 % , 
    Output:
    
Conclusions BLVR offers early promise in the palliation of advanced emphysema .