Evaluation of bronchoscopic lung volume reduction coil treatment results in patients with severe emphysema

Effect of Endobronchial Coils on Exercise Tolerance and Lung Functions in Patients with Severe Emphysema - A Retrospective Cohort Study of 48 Patients

Background

Lung volume reduction with endobronchial coils treatment (ECT), for patients with severe emphysema, has shown modest improvement in exercise capacity and lung functions in clinical trials, yet the benefit of this procedure is still unclear.

Methods

We conducted a multicenter retrospective cohort study including all patients who underwent ECT in Israel and a propensity score matched control group of patients with chronic obstructive pulmonary disease (COPD) that were treated with usual care. The primary outcome was six-minute walk test distance (6MWTD), secondary outcomes were lung function tests and patient survival.

Results

Overall, 46 patients were included in the ECT group. Their mean 6MWTD at baseline and at 6 and at 24 months post procedure was 331.0±101.4, 372.9±76.8 and 338.8±104.8, respectively (overall P=0.04, pairwise comparison: baseline to 6 months (P=0.1), baseline to 24 months (P=1.0)). Mean FEV1 values at baseline and at 6 and at 24 months post procedure were 0.86±0.38, 0.92±0.37 and 0.82±0.36 liters, respectively (overall P=0.003, pairwise comparison: baseline to 6 months (P=0.04), baseline to 24 months (P=0.75)). The median 6MWTD for the ECT and control groups at 24 months were 333.0 (262.5–390) and 280 (210–405), respectively (P=0.16). There was no difference in overall survival (P=0.84). Heterogenous emphysema was a significant predictor of treatment success in univariate analysis (p=0.004).

Conclusion

Lung volume reduction with endobronchial coils may improve the exercise capacity and FEV1 of COPD patients. However, the majority of the effect was diminished after 24 months. The current state of evidence does not support regulatory approval of ECT and warrant its use only after consideration of the benefit-harm ratio in a highly selected patient population.

The Effects of Endobronchial Coil Therapy on Right Ventricular Functions

Lung hyperinflation is an important therapeutic target in symptomatic emphysema patients. Endobronchial therapies that reduce end-expiratory lung volume are increasingly being used in advanced cases. However, there is paucity of data regarding the effects of these therapies on the heart functions. The aim of this study is to evaluate the right ventricular functions before and after the procedure in patients who underwent endobronchial coil therapy (EBCT).Patients who were between 18 and 80 years of age and scheduled for EBCT with GOLD 3-4 were enrolled in the study. Right heart functions were evaluated using MPI, TAS, TAPSE. Right atrium area and maximum velocity of tricuspid regurgitation were also noted.A total of 23 patients were enrolled in the study. 21 patients underwent bilateral intervention, while only 2 patients received unilateral treatment. There was an improvement in MPI (0.49 ± 0.15 vs 0.39 ± 0.11, p < 0.001) and TAS (11.6 (9 - 15) vs 13.2 (9.80 - 17.0), p = 0.001). Peak TRV (2.52 ± 0.6, 2.38 ± 0.6, p = 0.02) and PASP values were lower in the post-operative period (41.15 ± 5.94 vs 36.83 ± 8.01 p = 0.019).In this current study, we found improved echocardiographic RtV parameters in patients who received EBCT treatment.

Effects of Bronchoscopic Lung Volume Reduction Coil Treatment on Arterial Blood Gases

BACKGROUND

Bronchoscopic lung volume reduction (BLVR) coil treatment is an increasingly used treatment modality for selected severe emphysema patients in recent years. Emphysema causes dynamic hyperinflation, loss of elastic recoil, air trapping, and decreased exercise capacity in advanced stages. This process progresses over time, leading to hypoxic and hypercapnic respiratory failure. The goal of this study is to elucidate the effects of BLVR coil treatment on arterial blood gas parameters in severe emphysema patients with respiratory failure.

METHODS

This is a retrospective study performed at a single pneumology center in Turkey. In total, this study included 39 patients diagnosed with severe emphysema who underwent bilateral BLVR coil treatment according to the general inclusion and exclusion criteria in the literature. The patients baseline and 12-month data were collected from medical records.

RESULTS

Twelve months after BLVR coil treatment, significant improvements were observed in patients' pulmonary function tests, an increase in partial pressure of oxygen in arterial blood (PaO2) from 58.05±9.36 to 73.82±13.3 (P<0.000) and decrease in partial pressure of carbon dioxide in arterial blood (PaCO2) of hypercapnic patients (from 51.60±4.1 to 46.55±6.6 mm Hg; P=0.001).

CONCLUSION

BLVR coil treatment is reliable and effective in emphysema patients who have hypoxic or mild hypercapnic respiratory failure. Besides improving lung function, BLVR coil treatment can significantly increase PaO2 and decrease PaCO2 in the medium term.

A New-Designed Lung-Bending Device for Bronchoscopic Lung Volume Reduction of Severe Emphysema: A Feasibility Study in Pigs

BACKGROUND

Bronchoscopic therapies are less invasive alternatives of surgical lung volume reduction for severe emphysema. Bending of lung tissue by implanting metallic coils into bronchi is one of the procedures. A new-designed device with a similar rationale, Reverser, has been developed with some improvements.

OBJECTIVES

The aim of the study was to evaluate the safety and feasibility of the Reversers.

METHODS

Twelve healthy pigs were randomly divided into 3 groups (groups A, B, and C). The Reversers were implanted bronchoscopically into the selected airways using a proprietary delivery system. Physical examination, chest fluoroscopy, computed tomography (CT) scans, and bronchoscopic observations were performed before implantation and during the follow-up period. Necropsy was performed respectively at 1 month (group A), 3 months (group B), and 6 months (group C) after implantation.

RESULTS

A total of 47 Reversers were implanted successfully. The procedure was feasible and well tolerated by all pigs. No severe complications, such as pneumothorax, abscesses, and airway hemorrhage, were found. No unintended injuries or death occurred. Mild granulation and inflammation were observed in the airway wall. Opacities around Reversers were shown on CT scans in some pigs. In the pigs with opacities, histological evaluation revealed widened alveolar septa due to inflammatory cell infiltration in the vicinity of the Reversers. On the analysis of CT data, there was a trend for volume reduction of the treated lung at 1 and 3 months after treatment compared with baseline.

CONCLUSIONS

This study showed that Reversers were safe and feasible for bronchoscopic lung volume reduction in pigs.

Endobronchial coils in treatment of advanced emphysema: A single center experience

Background

This study aims to present our experience with endobronchial coils in patients who underwent endobronchial lung volume reduction due to advanced emphysema.

Methods

The study included 46 patients (45 males, 1 female; mean age 61.7±8 years; range, 43 to 80 years) who underwent endobronchial lung volume reduction with endobronchial coils for advanced emphysema. Patients" age, gender, pulmonary function tests, post-treatment morbidity, mortality, pre- and post-treatment (6 months) six-minute walking distance, modified Medical Research Council dyspnea scores, chronic obstructive pulmonary disease assessment test and Hospital Anxiety and Depression Scale scores were recorded.

Results

Patients had an average of 65 pack/year smoking history. An average of 11 (range, 9-15) coils were placed per lobe (right upper lobe=35, left upper lobe=19, right lower lobe=2, left lower lobe=4). Mean follow-up duration was 12.6 months (±5.6 months). Post-treatment forced expiratory volume in one second, residual volume and six-minute walking distance values were improved with statistical significance. Also, significant improvement was seen in quality of life, quantified by modified Medical Research Council, chronic obstructive pulmonary disease assessment test and Hospital Anxiety and Depression Scale scores. While no immediate major postoperative complications occurred, three patients developed chronic obstructive pulmonary disease exacerbation, two developed pneumonia, and one developed recurrence of previous neurologic disorder within 30 days.

Conclusion

Endobronchial coil administration provides lower morbidity and mortality compared to lung volume reduction surgery as well as significant improvement in pulmonary functions and quality of life in selected patients with advanced emphysema.

Importance of bronchoscopic lung volume reduction coil therapy in potential candidates for lung transplantation

Bronchoscopic lung volume reduction (BLVR) coil treatment is a alternative and promising treatment modality for selected severe emphysema patients. The main indication of this treatment modality is a forced expiration volume in one second (FEV1) of 15-45% and a residual volume (RV) > 175%. The aim of this study was to investigate the efficacy of BLVR coil therapy in patients with end-stage emphysema who were potential candidates for lung transplantation and had FEV1 values less than 25%. Twenty-one patients who underwent bilateral BLVR coil therapy between September 2013 and May 2015 were retrospectively reviewed. We compared the changes in clinical and laboratory parameters at the baseline and 12 months after the treatment. Twelve months after the bilateral BLVR coil treatment, we observed an average increase in FEV1 (110 mL and 4.6%), a decrease in residual volume (660 mL and 33%), and an increase in 6-minute walk tests (67 m). The most common complications were chronic obstructive pulmonary disease exacerbation (47.6%) and pneumonia (23.8%). All patients tolerated the general anesthesia and procedure very well. BLVR coil therapy is safe and effective in patients with end-stage emphysema, who are potential candidates for lung transplantation within a short to medium period. The complication rates of this treatment were not different from those of the other coil treatments, and the improvements in the clinical parameters after the treatment resulted in gaining time for lung transplantation. Future research for evaluating the long-term efficacy of BLVR coil therapy in these patients is essential.

Endobronchial Coils for Endoscopic Lung Volume Reduction: Best Practice Recommendations from an Expert Panel

Endobronchial coils are an additional treatment option for lung volume reduction in patients with severe emphysema. Patient selection should be focused on patients with severe emphysema on optimal medical therapy and with evidence of severe hyperinflation. The technique is suitable in a broad range of patients with emphysema; however, patients with paraseptal emphysema, large focal (giant) bullae, significant co-morbidity and airway-predominant disease should be avoided. Treatment involves placing between 10 and 14 coils by bronchoscopy in the selected treatment lobe, with 2 lobes being treated sequentially. Lobe selection for treatment should be based on quantitative computed tomography, and the lobes with the greatest destruction should be targeted (excluding the right middle lobe). The treatment results in an improvement in pulmonary function, exercise performance and quality of life, particularly in patients with severe hyperinflation (residual volume > 200% predicted) and upper-lobe heterogeneous emphysema, but will also be of benefit in lower-lobe predominant and homogeneous emphysema. Finally, it has an acceptable safety profile, although special attention has to be paid to coil-associated opacity which is an inflammatory response that occurs in some patients treated with endobronchial coils.

Bronchoscopic Lung Volume Reduction: A 2018 Review and Update

Bronchoscopic lung volume reduction (BLVR) procedure has expanded the treatment spectrum of patients with end-stage emphysema. These treatments include valve, coil, thermal vapor ablation, bio-lung volume reduction, targeted lung denervation, and airway bypass stent. This short review provides an up-to-date information on BLVR treatments, their clinical benefits, and an overview of complications. BLVR treatments generally affect dyspnea by reducing hyperinflation and residual volume (RV). Benefits of treatment are associated with improvement in lung function parameters (forced expiration volume in the first second, total lung capacity, RV, and 6-minute walking test) and quality of life. Serious potential pulmonary complications, such as pneumothorax, pneumonia, respiratory failure, and chronic obstructive pulmonary disease exacerbation, may also occur after BLVR treatment. In addition to these, low-cost BLVR methods, such as autologous blood and fibrin glue, are in the developmental stage. Bronchoscopic lung volume reduction treatments are a promising method with positive results for patients with severe emphysema. The widespread use of these techniques, inadequate selection of patients, and non-critical and, therefore, unsuccessful use of BLVR in non-specialist centers lead to a false negative impression of the effectiveness of these techniques. In addition to these considerations, it is obvious that these treatments, which are quite expensive, are burdening social health systems. The reduction of costs or the development of lower-cost treatment methods is important for the future and for the availability of treatments.

Bronchoscopic lung volume reduction: recent updates

Emphysema causes significant morbidity and mortality, incurring both financial and psychosocial costs. Alternatives to medical therapy and surgical lung volume reduction surgery (LVRS) have increased interest in bronchoscopic techniques. Bronchoscopic lung volume reduction (BLVR) is still in its infancy and additional trials and follow-up are critical. However, several new randomized clinical trials (RCTs) have demonstrated improvement in lung function, quality of life and exercise capacity in select patients receiving endobronchial valves and coil therapy. This article highlights recent data regarding bronchoscopic treatment of emphysema.

Bone Marrow-Derived Mononuclear Cell Therapy in Papain-Induced Experimental Pulmonary Emphysema

Murine papain-induced emphysema is a model that reproduces many of the features found in patients. Bone marrow-derived mononuclear cells (BMMC) have already been used to repair the alveolar epithelium in respiratory diseases, but not in the papain model. Thus, we hypothesized that BMMC could prevent the pathophysiological processes in papain-induced experimental emphysema. Female BALB/c mice received intratracheal instillation of 50 μL of saline (S groups) or papain (P groups, 10 IU/50 μl of saline) on days 1 and 7 of the experimental protocol. On the 14th day, 2 × 10⁶ BMMC of male BALB/c mice (SC21 and PC21) or saline (SS21 and PS21) were injected by the jugular vein. Analyses were done on days 14 (S14 and P14) and 21 (SS21, PS21, SC21, and PC21) of the protocol. qPCR evaluated the presence of the Y chromosome in the lungs of BMMC recipient animals. Functional residual capacity (FRC), alveolar diameter, cellularity, elastic fiber content, concentrations of TNF-α, IL-1β, IL-6, MIP-2, KC, IFN-γ, apoptosis, mRNA expression of the dual oxidase (DUOX1 and DUOX2), production of H₂O₂ and DUOX activity were evaluated in lung tissue. We did not detect the Y chromosome in recipients' lungs. FRC, alveolar diameter, polymorphonuclear cells (PMN) and levels of KC, MIP-2, and IFN-γ increased in P14 and PS21 groups; the changes in the latter were reverted by BMMC. TNF-α, IL-1β e IL-6 were similar in all groups. The amount of elastic fibers was smaller in P14 and PS21 than in other groups, and BMMC did not increase it in PC21 mice. PS21 animals showed increased DUOX activity and mRNA expression for DUOX1 and 2. Cell therapy reverted the activity of DUOX and mRNA expression of DUOX1. BMMC reduced mRNA expression of DUOX2. Apoptosis index was elevated in PS21 mice, which was reduced by cell therapy in PC21. Static compliance, viscoelastic component of elastance and pressure to overcome viscoelasticity were increased in P14 and PS21 groups. These changes and the high resistive pressure found on day 21 were reverted by BMMC. In conclusion, BMMC showed potent anti-inflammatory, antiapoptotic, antioxidant, and restorative roles in papain-triggered pulmonary emphysema.