Modifying Post-Operative Medical Care after EBV Implant May Reduce Pneumothorax Incidence

When Treatment of Pulmonary Emphysema with Endobronchial Valves Did Not Work: Evaluation of Quantitative CT Analysis and Pulmonary Function Tests Before and After Valve Explantation

Purpose

To investigate changes in quantitative CT analysis (QCT) and pulmonary function tests (PFT) in pulmonary emphysema patients who required premature removal of endobronchial valves (EBV).

Patients and Methods

Our hospital’s medical records listed 274 patients with high-grade COPD (GOLD stages 3 and 4) and pulmonary emphysema who were treated with EBV to reduce lung volume. Prior to intervention, a complete evaluation was performed that included quantitative computed tomography analysis (QCT) of scans acquired at full inspiration and full expiration, pulmonary function tests (PFT), and paraclinical findings (6-minute walking distance test (6MWDT) and quality of life questionnaires). In 41 of these 274 patients, EBV treatment was unsuccessful and the valves had to be removed for various reasons. A total of 10 of these 41 patients ventured a second attempt at EBV therapy and underwent complete reevaluation. In our retrospective study, results from three time points were compared: Before EBV implantation (BL), after EBV implantation (TP2), and after EBV explantation (TP3). QCT parameters included lung volume, total emphysema score (TES, ie, the emphysema index) and the 15th percentile of lung attenuation (P15) for the whole lung and each lobe separately. Differences in these parameters between inspiration and expiration were calculated (Vol. Diff (%), TES Diff (%), P15 Diff (%)). The results of PFT and further clinical tests were taken from the patient’s records.

Results

We found persistent therapy effect in the target lobe even after valve explantation together with a compensatory hyperinflation of the rest of the lung. As a result of these two divergent effects, the volume of the total lung remained rather constant. Furthermore, there was a slight deterioration of the emphysema score for the whole lung, whereas the TES of the target lobe persistently improved.

Conclusion

Interestingly, we found evidence that, contrary to our expectations, unsuccessful EBV therapy can have a persistent positive effect on target lobe QCT scores.

Early Spirometry Following Bronchoscopic Lung Volume Reduction with Endobronchial Valves

Bronchoscopic lung volume reduction (BLVR) by endobronchial valve (EBV) implantation has been shown to improve dyspnea, pulmonary function, exercise capacity, and quality of life in highly selected patients with severe emphysema and hyperinflation. The most frequent adverse event is a pneumothorax (PTX), occurring in approximately one-fifth of the cases due to intrathoracic volume shifts. The majority of these incidents are observed within 48 h post-procedure. However, the delayed occurrence of PTX after hospital discharge is a matter of concern. There is currently no approved concept for its prevention. Particularly, it is unknown whether and when respiratory manoeuvers such as spirometry post EBV treatment are feasible and safe. As per standard operating procedure at the University Hospital Zurich, early spirometry is scheduled after BLVR and prior to the discharge of the patient in order to monitor treatment success. The aim of our retrospective study was to investigate the feasibility and safety of early spirometry. In addition, we hypothesized that early spirometry could be useful to identify patients at risk for late PTX, which may occur after hospital discharge. All patients who underwent BLVR using EBVs between January 2018 and January 2020 at our hospital were enrolled in this study. After excluding 16 patients diagnosed post-procedure with PTX and four patients for other reasons, early spirometry was performed in 61 cases. There was neither a clinically relevant PTX during or after early spirometry nor a late PTX following hospital discharge. In conclusion, we found early spirometry, conducted not sooner than three days following EBV treatment, to be feasible and safe. Furthermore, early spirometry seems to be a useful predictor for successful BLVR, and it may help to decide whether a patient can be discharged. Given the small sample size and the retrospective design of our study, a prospective study that includes routine chest imaging after early spirometry to definitively exclude PTX is needed to recommend early spirometry as part of the standard protocol following EBV treatment.

Surgical Interventions for COPD

Chronic obstructive pulmonary disease (COPD) treatment is aimed at managing the disease rather than cure, with a focus on improving quality of life and decreasing exacerbations. Interventional therapies, including lung volume reduction surgery, bullectomy, lung transplantation, and bronchoscopic lung volume reduction treatment using endobronchial valves, are treatment options for patients with COPD who are symptomatic due to hyperinflation despite optimal medical management. We will review the current literature to provide a comprehensive summary of the currently available scientific data, discuss typical treatment-related side effects, and evidence-based management approach and recommendations for patient selection in clinical practice.

Expert Statement: Pneumothorax Associated with One-Way Valve Therapy for Emphysema: 2020 Update

For selected patients with advanced emphysema, bronchoscopic lung volume reduction with one-way valves can lead to clinically relevant improvements of airflow obstruction, hyperinflation, exercise capacity, and quality of life. The most common complication of this procedure is pneumothorax with a prevalence of up to ±34% of the treated patients. Patients who develop a pneumothorax also experience meaningful clinical benefits once the pneumothorax is resolved. Timely resolution of a post-valve treatment pneumothorax requires skilled and adequate pneumothorax management. This expert panel statement is an updated recommendation of the 2014 statement developed to help guide pneumothorax management after valve placement. Additionally, mechanisms for pneumothorax development, risk assessment, prevention of pneumothorax, and outcomes after pneumothorax are addressed. This recommendation is based on a combination of the current scientific literature and expert opinion, which was obtained through a modified Delphi method.

Role of Imaging in Bronchoscopic Lung Volume Reduction Using Endobronchial Valve: State of the Art Review

Chronic obstructive pulmonary disease (COPD) is becoming one of the leading causes of mortality and morbidity throughout the world. The National Emphysema Treatment Trial demonstrated that lung volume reduction surgery can improve pulmonary function, exercise capacity, and quality of life in select subgroups of patients with COPD. In recent years, few bronchoscopic lung volume reduction (BLVR) procedures have undergone clinical trials with the goal of establishing an effective and safe alternative approach for reducing hyperinflation in patients with severe emphysema who are symptomatic despite optimal medical management, but are poor surgical candidates. Of these BLVR procedures, only deployment of 1-way endobronchial valves (EBVs) has the largest pool of scientific data available to date to support its clinical utility. Two EBV systems have been food and drug administration-approved within the last year to meet the clinical demands of this select group of patients with COPD. On the basis of the results of multiple randomized clinical trials, the recommendations of the original 2016 Expert Panel Report on BLVR usage criteria of EBV have been updated in 2019. The outcome of EBV therapy is maximized in certain image-based COPD phenotypes. Imaging plays a major role in patient selection, target lobe identification, and in the management of postprocedural adverse events. With the expected widespread use of EBV therapy in the coming years, knowledge and familiarity of the Role of Imaging in BLVR using EBVs is essential for radiologists attempting to make meaningful contribution toward improving clinical outcomes.

[Imaging before and after endoscopic lung volume reduction]

The treatment of symptomatic lung emphysema by lung volume reduction has become established over the last 15 years. While surgical partial lung resection has profited from improved and less invasive surgical techniques, various endoscopic interventional procedures have been developed and are now available for use. All treatment approaches are dependent on individual anatomical variants and a regional distribution of the lung emphysema, which is why no procedure can be designated as the gold standard for all patients. High-resolution computed tomography can be qualitatively evaluated and provides decisive information for treatment, which is why radiologists play a particularly important role in treatment planning and aftercare of an intervention for reduction of the lung volume. This article presents the various endoscopic techniques, names the demands of the treating physician on the advising radiologist and finally describes how a treatment decision is derived from the results obtained.

Anaesthetic management for endobronchial valve insertion: lessons learned from a single centre retrospective series and a literature review

Background

Endoscopic lung volume reduction using one or more endobronchial valves is a treatment option for a select group of patients with severe emphysema. Patients presenting for this procedure pose various challenges to the anaesthetist; in addition to their lung condition, they are often elderly with multiple comorbidities. The procedure is usually performed outside the operating room. Monitored anaesthesia care with intravenous sedation, and general anaesthesia with an endotracheal tube have both been described for these procedures, aiming for adequate ventilation and haemodynamic stability.

Methods

We present our experience on 20 of these procedures in relation to the anaesthetic techniques employed and discuss the perioperative challenges involved in managing these cases.

Results

Twenty one planned endobronchial valve insertion procedures were identified on 18 patients. There were ten cases of monitored anaesthesia care with sedation and 10 cases which used general anaesthesia with an endotracheal tube. Two have been excluded; one had features of anaphylaxis and the procedure was abandoned, and the other required conversion from monitored anaesthesia care to general anaesthesia with endotracheal tube.

Conclusions

Both monitored anaesthesia care with sedation and general anaesthesia with endotracheal tube were well tolerated during endobronchial valve insertion procedures. General anaesthesia with endotracheal tube may offer better interventional conditions, patient comfort and reduced anaesthetic time.

The REACH Trial: A Randomized Controlled Trial Assessing the Safety and Effectiveness of the Spiration® Valve System in the Treatment of Severe Emphysema

BACKGROUND

Chronic obstructive pulmonary disease (COPD) has become a leading cause of morbidity and mortality in China, with tobacco smoke, air pollution, and occupational biohazards being the major risk factors.

OBJECTIVES

The REACH trial is a multicenter, prospective, randomized controlled trial undertaken in China to assess the safety and effectiveness of the Spiration® Valve System (SVS) compared to standard medical care in COPD patients with severe emphysema.

METHODS

Patients with severe airflow obstruction, hyperinflation, and severe dyspnea with interlobar fissure integrity were evaluated for enrollment. A total of 107 subjects were randomized in a 2: 1 allocation ratio to either the treatment group (SVS valves and medical management) or the control group (medical management alone).

RESULTS

The 3-month primary endpoint showed statistically significant improvement in forced expiratory volume in 1 s in the treatment group compared to the control group (0.104 ± 0.18 vs. 0.003 ± 0.15 L, p = 0.001), with the difference being durable through 6 months. Statistically significant target lobe volume reduction was achieved at 3 months (mean change 684.4 ± 686.7 mL) and through 6 months (757.0 ± 665.3 mL). Exercise function and quality of life measures improved in the treatment group, but showed a deterioration in the control group. The serious adverse event (SAE) rate was 33% in the treatment group and 24.2% in the control group. The predominance of SAEs were acute exacerbations of COPD in both groups. There was 1 death in the control group and no deaths in the treatment group.

CONCLUSION

The SVS represents a novel approach for the treatment of severe emphysema with a clinically acceptable risk-benefit profile.

Valve therapy in patients with emphysematous type of chronic obstructive pulmonary disease (COPD): from randomized trials to patient selection in clinical practice

In recent years a number of endoscopic methods have emerged to treat patients with severe emphysematous type of chronic obstructive pulmonary disease (COPD), who are primarily symptomatic due to hyperinflation despite optimal medical management. Of these techniques, implantation of endobronchial one-way valves into targeted airways of isolated emphysematous lobes appears to be one of the most promising innovations. Results from randomized controlled trials of valve therapy for emphysema show consistent benefits in terms of lung function, exercise capacity, symptoms, and quality of life. This review aims to provide a comprehensive summary of the currently available scientific data, discussion of typical treatment related side effects, and recommendations for patient selection in clinical practice.

Complications after bronchoscopic lung volume reduction

Bronchoscopic lung volume reduction (BLVR) has been demonstrated an efficient and safe alternative to surgery in multiple randomized trials and retrospective cohort studies. However, despite its minimal invasiveness BLVR is not without potential harm. Complications and their incidents differ significantly between the individual BLVR techniques (valves, coils, vapour or sealant) which are bearing varying device- and intervention-dependent risks. Interventional pulmonologists must be aware of potential side effects and their management to anticipate and ensure highest quality treatment of the severely ill emphysema patient.

Endoscopic approaches for treating emphysema

INTRODUCTION

Surgical treatment of severe pulmonary emphysema has so far been associated with relatively high perioperative morbidity and mortality. In the past two decades, novel approaches to lung volume reduction and alternative minimally invasive endoscopic techniques have been developed. This review presents the different techniques (blocking and nonblocking) available until present as well as the appropriate patient selection and possible complications. Areas covered: All available randomized controlled trials (RCTs) have been evaluated. The only blocking technique is the reversible valve implantation. It results in lobar volume reduction and clinical benefit in emphysema patients with absent interlobar collateral ventilation and its efficacy has been confirmed in various RCTs. Non-blocking techniques that are independent of collateral ventilation include the partially irreversible coil implantation leading to parenchymal compression, the irreversible bronchoscopic thermal vapor ablation, and the polymeric lung volume reduction both inducing inflammatory reaction. These methods have been up to date examined in a few RCTs only. Finally, the targeted lung denervation aims at sustainable bronchodilation by ablation of parasympathetic pulmonary nerves. Expert commentary: Future studies must address the predictors of clinical outcome as well as the reduction of complications to improve both outcome and safety.

Interventional pulmonology in chronic obstructive pulmonary disease

PURPOSE OF REVIEW

Chronic obstructive pulmonary disease (COPD) and emphysema are widespread diseases associated with progressive dyspnea because of airflow limitation and hyperinflation. Fundamental therapeutic strategies consist of pulmonary rehabilitation, pharmacotherapy, long-term oxygen therapy, noninvasive ventilation, and surgical therapeutic approaches.

RECENT FINDINGS

In the last 14 years, endoscopic therapeutic modalities emerged as a substantial part of severe COPD and emphysema treatment. Techniques of the endoscopic lung volume reduction (ELVR) aim at reduction of hyperinflation. Thereby, the reversible valve implantation of which the efficacy was confirmed in various randomized controlled trials (RCT) results in lobar volume reduction and clinical benefit in emphysema patients with absent interlobar collateral ventilation. Nonblocking ELVR methods that are independent of collateral ventilation include the partially irreversible coil implantation leading to parenchymal compression, the irreversible bronchoscopic thermal vapor ablation and polymeric lung volume reduction both inducing inflammatory reaction. The nonblocking methods have been examined in only a few RCTs. The targeted lung denervation as a novel bronchoscopic therapy for COPD patients aims at sustainable bronchodilation by ablation of parasympathetic pulmonary nerves.

SUMMARY

The review summarizes the various endoscopic treatment approaches for managment of COPD and emphysema, their mechanism of action, their complications and the current available results of the most important RCTs.

Pleural Adhesion Assessment as a Predictor for Pneumothorax after Endobronchial Valve Treatment

BACKGROUND

Pneumothorax after bronchoscopic lung volume reduction using one-way endobronchial valves (EBVs) in patients with advanced emphysema occurs in approximately 20% of patients. It is not well known which factors predict the development of pneumothorax.

OBJECTIVE

To assess whether pleural adhesions on pretreatment high-resolution computed tomography (HRCT) scans are associated with pneumothorax occurrence after EBV treatment.

METHODS

HRCT scan analyses were performed on all patients who received EBV treatment in a randomized controlled trial. Three blinded readers scored adhesions by number and by measuring the longest axis of each pleural adhesion in the treated lung. The Pleural Adhesion Score (PAS) was calculated by adding 1 point for each small pleural lesion (<1 mm), 5 points for each medium-sized lesion (1-5 mm), and 10 points for each large lesion (>5 mm).

RESULTS

The HRCT scans of 64 treated patients were assessed, of whom 14 developed pneumothorax. Patients who developed pneumothorax had a higher median number of pleural adhesions, 2.7 (IQR 1.9-4) compared to 1.7 (1-2.7) adhesions in the group without pneumothorax (p < 0.01). The PAS in the group with pneumothorax was higher compared to that in the group without: 14.3 (12.4-24.1) versus 6.7 (3.7-11.2) (p < 0.01). A threshold PAS of ≥12 was associated with a higher risk of pneumothorax (OR 13.0, 95% CI 3.1-54.9). A score <12 did not rule out the occurrence of pneumothorax.

CONCLUSION

A higher number of pleural adhesions on HRCT with a subsequent higher PAS in the treated lung is associated with a higher occurrence of pneumothorax after EBV treatment.

The bronchoscopic interventions for chronic obstructive pulmonary disease according to different phenotypes

Bronchoscopic interventions are valuable adjuncts to the pharmacologic therapy for chronic obstructive pulmonary disease (COPD). But different phenotypes of COPD patients showed different clinical responses to the same or similar therapy. The optimal selection of bronchoscopic interventions for COPD patients also needs to be based on the phenotypes. According to the different phenotypes, novel interventional pulmonology techniques which were used for COPD treatments in daily clinical practice or clinical trials have been described extensively throughout our current review.

Novel Technologies in Endoscopic Lung Volume Reduction

Endoscopic lung volume reduction (ELVR) presents an effective therapy in patients with advanced emphysema. Different ELVR techniques are available differing in mechanism of action, degree of reversibility and safety. Precise patient selection with respect to pulmonary function test, emphysema distribution, and collateral ventilation are prerequisites for a successful use of the various ELVR techniques. To date, there are only a few randomized controlled trials for bronchoscopic therapy in patients with chronic obstructive pulmonary disease, so the various techniques should be performed within clinical trials or registry studies.

Endobronchial Valves for Endoscopic Lung Volume Reduction: Best Practice Recommendations from Expert Panel on Endoscopic Lung Volume Reduction

Endoscopic lung volume reduction (ELVR) is being adopted as a treatment option for carefully selected patients suffering from severe emphysema. ELVR with the one-way endobronchial Zephyr valves (EBV) has been demonstrated to improve pulmonary function, exercise capacity, and quality of life in patients with both heterogeneous and homogenous emphysema without collateral ventilation. In this "expert best practices" review, we will highlight the practical aspects of this therapy. Key selection criteria for ELVR are hyperinflation with a residual volume >175% of predicted, forced expiratory volume <50% of predicted, and a 6-min walking distance >100 m. Patients with repeated infectious complications, severe bronchiectasis, and those with unstable cardiovascular comorbidities should be excluded from EBV treatment. The procedure may be performed with either conscious sedation or general anesthesia and positive pressure mechanical ventilation using a flexible endotracheal tube or a rigid bronchoscope. Chartis and EBV placement should be performed in 1 procedure when possible. The sequence of valve placement should be orchestrated to avoid obstruction and delivery of subsequent valves. If atelectasis has not occurred by 1 month after procedure, evaluate valve position on CT and consider replacing the valves that are not optimally positioned. Pneumothorax is a common complication and typically occurs in the first 2 days following treatment. A management algorithm for pneumothorax has been previously published. Long-term sequelae from EBV therapy do occur but are easily manageable.

Clinical and radiological outcome following pneumothorax after endoscopic lung volume reduction with valves

INTRODUCTION

Valve implantation has evolved as a therapy for patients with advanced emphysema. Although it is a minimally invasive treatment, it is associated with complications, the most common being pneumothorax. Pneumothorax occurs due to the rapid target lobe volume reduction and may be a predictor of clinical benefit despite this complication.

OBJECTIVE

The objective of this study was to conduct an exploratory data analysis of patients who developed a pneumothorax following endoscopic valve therapy for emphysema.

MATERIALS AND METHODS

This study performed a retrospective evaluation of pneumothorax management and the impact of pneumothorax on clinical outcomes in 70 patients following valve therapy in 381 consecutive patients.

RESULTS

Pneumothorax rate following valve therapy was 18%. Pneumothorax management consisted of chest tube insertion, valve removal, and surgical intervention in 87% (61/70), 44% (31/70), and 19% (13/70) of the patients, respectively. Despite pneumothorax, patients experienced modest but significant improvements in lung function parameters (forced expiratory volume in 1 second: 55±148 mL, residual volume: -390±964 mL, total lung capacity: -348±876; all P<0.05). Persistent lobar atelectasis 3 months after recovering from pneumothorax, which was associated with relevant clinical improvement, was observed in only 21% (15/70) of the patients.

CONCLUSION

Pneumothorax is a frequent severe complication following valve therapy that requires further intervention. Nevertheless, the pneumothorax does not impair the clinical status in the majority of patients. Patients with lobar atelectasis benefit after recovering from pneumothorax in terms of lung function parameters.

Bilateral Endoscopic Lung Volume Reduction in Patients with Severe Emphysema

Reducing hyperinflated areas in chronic obstructive pulmonary disease, either surgically or endoscopically, leads to improvement of functional parameters. It is unclear if bilateral treatment with endobronchial valves (EBV) aiming at total lobar occlusion is beneficial. The aim of this study was to assess the results after staged bilateral endoscopic treatment with EBV. This is a retrospective analysis of patients with severe airflow obstruction, who were treated bilaterally with EBV in two stages, aiming at subsequent atelectasis. Pre- and postintervention lung function parameters, the 6-minute walk test (6-MWT), complications, and follow-up were recorded. Sixteen patients were treated bilaterally in two stages. There was an overall improvement in lung function from baseline to second-treatment follow-up with an increase in FEV1 (23.57-29.21% of predicted) and a decrease in residual volume (299.21-240.10% of predicted) and total lung capacity (140.78-128.71% of predicted). The 6-MWT improved up to 54 m. After each procedure, 9 of 16 patients (56.25%) developed an atelectasis of the target lobe. Overall, pneumothorax occurred in 8 of 32 procedures (25%). No patient died. Patients benefitted from the first EBV treatment. The second treatment did not lead to marked improvements compared to the first treatment. Bilateral lung volume reduction with valves is possible; however, the current results seem not to justify bilateral valve treatment as a routine approach.

Status of and prospects for bronchoscopic lung volume reduction for patients with severe emphysema

Bronchoscopic lung volume reduction (BLVR) is a minimally invasive treatment for severe emphysema, providing treatment options for patients who are unable to undergo lung volume reduction surgery (LVRS) or lung transplantation. Current BLVR techniques include bronchoscopic volume reduction with valve implants, use of a lung volume reduction coil (LVRC), bronchoscopic thermal vapor ablation (BTVA), biological lung volume reduction (BioLVR), and use of airway bypass stents (ABS). To date, several randomized controlled trials of these bronchoscopic therapies have been conducted in patients with emphysema, and bronchoscopic volume reduction with valve implants remains the best approach thus far. Recent studies indicate that BLVR may be of great value in improving lung function, exercise capacity, and quality of life and that BLVR has the potential to replace conventional surgery for patients with severe emphysema. Optimal patient selection and the proper selection of the BLVR technique in accordance with patient characteristics are crucial to the success of BLVR. More multicenter, prospective, randomized controlled trials need to be conducted in the future to optimize the current selection strategy and evaluate the safety, efficiency, and long-term benefit of BLVR techniques.

Predictors of pneumothorax following endoscopic valve therapy in patients with severe emphysema

BACKGROUND

Endoscopic valve implantation is an effective treatment for patients with advanced emphysema. Despite the minimally invasive procedure, valve placement is associated with risks, the most common of which is pneumothorax. This study was designed to identify predictors of pneumothorax following endoscopic valve implantation.

METHODS

Preinterventional clinical measures (vital capacity, forced expiratory volume in 1 second, residual volume, total lung capacity, 6-minute walk test), qualitative computed tomography (CT) parameters (fissure integrity, blebs/bulla, subpleural nodules, pleural adhesions, partial atelectasis, fibrotic bands, emphysema type) and quantitative CT parameters (volume and low attenuation volume of the target lobe and the ipsilateral untreated lobe, target air trapping, ipsilateral lobe volume/hemithorax volume, collapsibility of the target lobe and the ipsilateral untreated lobe) were retrospectively evaluated in patients who underwent endoscopic valve placement (n=129). Regression analysis was performed to compare those who developed pneumothorax following valve therapy (n=46) with those who developed target lobe volume reduction without pneumothorax (n=83).

FINDING

Low attenuation volume% of ipsilateral untreated lobe (odds ratio [OR] =1.08, P=0.001), ipsilateral untreated lobe volume/hemithorax volume (OR =0.93, P=0.017), emphysema type (OR =0.26, P=0.018), pleural adhesions (OR =0.33, P=0.012) and residual volume (OR =1.58, P=0.012) were found to be significant predictors of pneumothorax. Fissure integrity (OR =1.16, P=0.075) and 6-minute walk test (OR =1.05, P=0.077) were also indicative of pneumothorax. The model including the aforementioned parameters predicted whether a patient would experience a pneumothorax 84% of the time (area under the curve =0.84).

INTERPRETATION

Clinical and CT parameters provide a promising tool to effectively identify patients at high risk of pneumothorax following endoscopic valve therapy.

Lung perfusion and emphysema distribution affect the outcome of endobronchial valve therapy

The exclusion of collateral ventilation (CV) and other factors affect the clinical success of endoscopic lung volume reduction (ELVR). However, despite its benefits, the outcome of ELVR remains difficult to predict. We investigated whether clinical success could be predicted by emphysema distribution assessed by computed tomography scan and baseline perfusion assessed by perfusion scintigraphy. Data from 57 patients with no CV in the target lobe (TL) were retrospectively analyzed after ELVR with valves. Pulmonary function tests (PFT), St George's Respiratory Questionnaire (SGRQ), and 6-minute walk tests (6MWT) were performed on patients at baseline. The sample was grouped into high and low levels at the median of TL perfusion, ipsilateral nontarget lobe (INL) perfusion, and heterogeneity index (HI). These groups were analyzed for association with changes in outcome parameters from baseline to 3 months follow-up. Compared to baseline, patients showed significant improvements in PFT, SGRQ, and 6MWT (all P≤0.001). TL perfusion was not associated with changes in the outcome. High INL perfusion was significantly associated with increases in 6MWT (P=0.014), and high HI was associated with increases in forced expiratory volume in 1 second (FEV1), (P=0.012). Likewise, there were significant correlations for INL perfusion and improvement of 6MWT (r=0.35, P=0.03) and for HI and improvement in FEV1 (r=0.45, P=0.001). This study reveals new attributes that associate with positive outcomes for patient selection prior to ELVR. Patients with high perfusions in INL demonstrated greater improvements in 6MWT, while patients with high HI were more likely to respond in FEV1.

Clinical review: Endobronchial valve treatment for emphysema

Breathlessness and impaired quality of life are prominent features in patients with severe emphysema even when conventional methods of treatment are optimal. Lung volume reduction using endobronchial management for emphysema has emerged as a new method to relieve symptoms and improve lung function tests in this group. The endobronchial valves (EBVs) are the most widely used treatment. This article outlines current criteria of patients' selection with literature review and evidence of efficacy. Complications of EBV insertion as well as current shortfalls of this method of treatment are also discussed.