Treatment of giant emphysamous bulla with endobronchial valves in patients with chronic obstructive pulmonary disease: a case series

From plugging air leaks to reducing lung volume: a review of the many uses of endobronchial valves

INTRODUCTION

One-way endobronchial valve treatment improves lung function, exercise capacity, and quality of live in patients with severe emphysema and hyperinflation. Other areas of therapeutic application include treatment of persistent air leak (PAL), giant emphysematous bullae, native lung hyperinflation, hemoptysis, and tuberculosis.

AREAS COVERED

In this review, we will assess the clinical evidence and safety of the different applications of one-way endobronchial valves (EBV).

EXPERT OPINION

There is solid clinical evidence for the use of one-way EBV for lung volume reduction in emphysema. Treatment with one-way EBV can be considered for the treatment of PAL. The application of one-way EBV for giant bullae, post lung transplant native lung hyperinflation, hemoptysis, and tuberculosis is under investigation and more research is required to investigate the efficacy and safety of these applications.

Bronchoscopic Treatment of Giant Emphysematous Bullae with Endobronchial Silicone Plugs

Purpose

Surgical bullectomy is the standard treatment of giant emphysematous bulla (GEB). However, bronchoscopic treatment should be considered as an alternative approach for patients who are unfit for surgical treatment. The study aimed to evaluate the clinical efficacy of endobronchial occlusion for the treatment of GEB using silicone plugs.

Methods

This retrospective study recruited four patients with GEB who were unsuitable for surgery. Preoperative planning was performed using high-resolution computed tomography and a virtual bronchoscopic navigation system. Customized silicone plugs were then placed in the target airway via bronchoscopy to cause GEB regression and atelectasis.

Results

All procedures were completed successfully in four patients. Three months after the procedures, compared with baseline, increases in the mean forced expiratory volume in 1 s (from 1.20 L/s to 1.33 L/s), forced vital capacity (from 2.63 L to 2.90 L), diffusion lung capacity for carbon monoxide (from 29% to 41% of the predicted value) and 6-minute walking test (from 412 m to 474 m) were observed. Additionally, the mean total lung capacity (from 6.80 L to 6.35 L), residual volume (from 3.97 L to 3.52 L), and St. George’s Respiratory Questionnaire scores (from 67 to 45) were all lower than baseline data.

Conclusion

Our preliminary results demonstrated that the endobronchial placement of silicone plugs could be a low-cost, safe, and effective choice for the treatment of GEB in surgically unfit patients.

Endoscopic Lung Volume Reduction with Autologous Blood: What is the Evidence?

Biological lung volume reduction (BioLVR) is a novel and low-cost endobronchial treatment method aimed at reducing the volume of the target lung lobe using biological agents, including fibrin-based hydrogel, fibrinogen, and autologous blood (AB) with thrombin. BioLVR induces local inflammation, resulting in acute airway obstruction, resorption atelectasis, fibrosis, and finally tissue remodeling by contraction of the target lobe and reduction in the lung volume, similar to the application of hot water vapor and foam. In addition, patients with severe impairment in lung function and quality of life may refuses to undergo surgery, resulting in limited treatment options. In such complex clinical scenarios, BioLVR with AB appears to be a good therapeutic option. These treatment modalities resulted in favorable outcomes in patients with heterogeneous and bullous emphysema, pulmonary lymphangioleiomyomatosis, and giant bullous lesions. AB applications result in functional improvement, improvement in the quality of life, decrease in dyspnea scores, and reduction in the size of bullae. Based on the available evidence, application of AB for lung volume reduction is minimally invasive and well tolerated by patients. There was no incidence of pneumothorax or mortality. This review aimed to investigate the benefits, complications, and future perspectives of AB application as BioLVR in the treatment of hyperinflated lung diseases.

Chartis System Corrected a Misjudged Location of a Giant Bulla Facilitating a Successful Bronchoscopic Bullectomy with Valves: A Case Report

The recommended standard treatment for giant bullae is surgical bullectomy. However, with a relatively high risk for perioperative morbidity and mortality, it is unsuitable for some patients. Recently, bronchoscopic bullectomy with one-way valves has shown efficacy and safety in some cases. Locating the giant bulla and confirming the negative collateral ventilation are essential for the bronchoscopic bullectomy with valves. Here, we report a case with a giant bulla using the Chartis System to correct the previous mislocation by the high-resolution computed tomography (HRCT), thus helping to achieve a great efficacy in the bronchoscopic bullectomy with valves. Our case suggests that bronchoscopic bullectomy with valves could be an effective and safe choice. Chartis system can be helpful in determining the location of a bulla when difficulty is encountered using HRCT.

Bronchoscopic lung volume reduction using an endobronchial valve to treat a huge emphysematous bullae: a case report

BACKGROUND

In patients with chronic obstructive pulmonary disease (COPD), bronchoscopic lung volume reduction (BLVR) techniques using unidirectional endobronchial valves improve lung function and increase exercise tolerance. BLVR treatment is included in the Global Initiative for Chronic Obstructive Lung Disease (GOLD) treatment guidelines for COPD patients without interlobar collateral ventilation. However, BLVR using an endobronchial valve has not been attempted in patients with giant bullae.

CASE PRESENTATION

We report successful and safe BLVR using an endobronchial valve in a patient with a huge bullous emphysema in the right middle lobe. A 65-year-old male was diagnosed with COPD 5 years prior and had a large bullae in the right middle lobe at that time. During regular follow-up, the symptoms of respiratory distress gradually worsened, and the size of the bullae gradually increased on computed tomography (CT). Therefore, we decided to treat the patient via BLVR using an unidirectional endobronchial valve. The Chartis system (Pulmonx, Inc., Palo Alto, CA) confirmed the absence of collateral ventilation of the right middle lobe. We successfully inserted an endobronchial valve into the right middle bronchus. After insertion, the bullae decreased dramatically in size, and the patient's symptoms and quality of life improved markedly.

CONCLUSION

This case supports recent suggestions that BLVR can serve as a good alternative treatment for appropriately selected patients.

Intrabullous Adhesion Pexia (IBAP) by Percutaneous Pulmonary Bulla Centesis: An Alternative for the Surgical Treatment of Giant Pulmonary Bulla (GPB)

Background and Objective

Most patients with giant pulmonary bulla (GPB) are treated by surgery; however, there is a subset for whom surgery is not a viable option, such as those with contraindications, or those unwilling to undergo operation. Therefore, an alternative minimally invasive method is desired for this subpopulation. The aim of this study was to explore an alternative procedure for treating GPB.

Methods

This was a prospective, nonrandomized, single-arm, unblinded study evaluating the efficacy and safety of intrabulla adhesion pexia (IBAP) procedure in GPB patients. The study was conducted between December 2004 and April 2017.

Results

There were 38 cases in 36 patients (33 males and 3 females) with the target GPB cavities varying in size (range, 10 cm × 7 cm × 5 cm to 15 cm × 8 cm × 30 cm (anteroposterior diameter × medial-lateral diameter × superoinferior diameter)). After IBAP treatment, the closure ratio of GPB in one month was 86.84% (33/38), while the dyspnea index significantly decreased from 4.11 ± 1.11 to 2.24 ± 1.15 (P < 0.01). In addition, the mean FEV1 (L) increased from 1.06 ± 0.73 to 1.57 ± 1.13 (P < 0.01), while RV (L) decreased from 2.77 ± 0.54 to 2.36 ± 0.38 (P < 0.01) and TLC (L) decreased from 6.46 ± 1.21 to 5.86 ± 1.08 (P < 0.01). Moreover, PaO₂ (mmHg) increased from 52.18 ± 8.31 to 68.29 ± 12.34, while the 6 MWD increased by 129.36% from 131.58 ± 105.24 to 301.79 ± 197.90 (P < 0.01). Collectively, these data indicated significant improvement in pulmonary function and exercise tolerance after IBAP treatment. Furthermore, no deaths occurred during IBAP treatment, and no cases of aggravated GPB relapse were reported during the 12-month follow-up period.

Conclusions

IBAP is a promising strategy for the treatment of GPB. Our findings demonstrated that IBAP had a noteworthy therapeutic effect, desirable safety, and ideal long-term efficacy for GPB.

The Clinical Significance of Collateral Ventilation

Oxygen delivery and carbon dioxide removal being critical to cell survival, mammals have developed collateral vascular and ventilation systems to ensure tissue viability. Collateral ventilation, defined as ventilation of alveoli via pathways that bypass normal airways, is present in humans and many other species. The presence of collateral ventilation can be beneficial in certain disease states, whereas its relative absence can predispose to other diseases. These well defined anatomical pathways contribute little to ventilation in normal humans, but modulate ventilation perfusion imbalance in a variety of diseases, including obstructive diseases, such as asthma and emphysema. These pathways can be affected by pharmaceuticals and inhaled gas compositions. The middle lobe and lingula, constrained by their isolated, segmental anatomy, have reduced collateral ventilation, which predisposes them to disease. Recently, attempts to improve the quality of life of patients with emphysema, by performing nonsurgical lung volume reduction via use of endobronchial valves, have led to mixed results, because the role of collateral ventilation in the success or failure of the procedure was not initially appreciated. This review describes the anatomical pathways of collateral ventilation, their physiology and relationship to disease states, their modulatory effects on gas exchange, treatment considerations, and their effect on diagnostic procedures.

Protective effect of autophagy on endoplasmic reticulum stress induced apoptosis of alveolar epithelial cells in rat models of COPD

During the present study, we explored the protective effects of autophagy on endoplasmic reticulum (ER) stress (ERS) induced apoptosis belonging to alveolar epithelial cells (AECs) in rat models with chronic obstructive pulmonary disease (COPD). Fifty-six 12-week-old male Sprague–Dawley (SD) rats were randomly assigned into the COPD group (rats exposed to cigarette smoke (CS)), the 3-methyladenine (3-MA) intervention group (COPD rats were administrated with 10 mg/kg autophagy inhibitors), the chloroquine (CQ)-intervention group (COPD rats were administrated 40 mg/kg CQ), and the control group (rats breathed in normal saline). The forced expiratory volume in 0.3 s/forced vital capacity (FEV_0.3/FVC%), inspiratory resistance (RI), and dynamic lung compliance (Cdyn) were measured and recorded. The expressions of PKR-like ER kinase (PERK) and CCAAT/enhancer-binding protein-homologous protein (CHOP) were detected by immunohistochemistry. The cell apoptotic rates of AECs were analyzed by terminal deoxynucleotidyl transferase (TdT) mediated dUTP-biotin nick end-labeling (TUNEL) staining. The expression levels of light chain 3 (LC3-II), p62, Beclin-1, ATG5, ATG7, Caspase-12, and Caspase-3 were detected by Western blotting. Results showed that the COPD group exhibited a lower FEV_0.3/FVC% and Cdyn, and a higher RI than the control group. Compared with the control group, the integrated optical density (IOD) values of PERK and CHOP, the apoptotic rate of AECs, and expressions of LC3-II, Beclin-1, ATG5, ATG7, Caspase-3, and Caspase-12 expressions were significantly higher, whereas p62 expression was significantly lower in the COPD group. Based on the results obtained during the present study, it became clear that the inhibition of autophagy could attenuate the ERS-induced apoptosis of AECs in rats with COPD.

Significant lung volume reduction with endobronchial valves in a patient despite the presence of microcollaterals masked by low-flow Chartis phenotype

Satisfactory functional outcomes following bronchoscopic lung volume reduction (BLVR) using endobronchial valves (EBVs) depend on the absence of collateral ventilation (CV) between the target and adjunct lobes. The Chartis system has proven to be useful for determining whether CV is present or absent, but this system can also erroneously indicate the absence of CV, which can lead to BLVR failure. Here, we describe low-flow Chartis phenotype in the target lobe resulted in difficult judgment of existence of CV. Consequently, BLVR with EBVs implanted into the right upper bronchus failed to reduce lung volume or induce atelectasis. Inserting another EBV into the right middle bronchus blocked the latent CV, which led to significant lung volume reduction in the right upper lobe (RUL) and right middle lobe (RML) and to improve the pulmonary function, 6-min walking distance, and St George respiratory questionnaire scores over a 2-week follow-up period. Low flow in the target lobe is a unique Chartis phenotype and represents the uncertainty of CV, which is a risk factor for the failure of BLVR using EBVs. Clinicians should be aware of this possibility and might be able to resolve the problem by blocking the RUL and RML between which the CV occurs.

Endobronchial valve to treat large bulla at right middle lobe in chronic obstructive pulmonary disease patients

We have used endobronchial valve (EBV) to treat large bulla at right middle lobe (RML) on three chronic obstructive pulmonary disease (COPD) patients and presented the clinical datum of three COPD patients with RML bulla. The improvement of lung function was significant on two patients, whose lung parenchyma was preserved well in lobes other than RML. On one patient, whose lung function did not show improvement after EBV treatment, the parenchyma of bilateral lungs was destructed heavily by chronic inflammation of COPD, and the RML bulla did not collapse because right major and/or minor fissures are incomplete. EBV may be used to treat large RML bulla in selected patients, whose parenchyma of other parts of the lung was conserved well and right major and minor fissures are complete.