Bronchoscopic Thermal Vapor Ablation Research Articles

Impact of bronchoscopic thermal vapor ablation on lung volume reduction in patients with emphysema: a meta-analysis

BackgroundBronchoscopic lung volume reduction (LVR) could significantly improve pulmonary function and quality of life in patients with emphysema. We aimed to assess the efficacy and safety of bronchoscopic thermal vapor ablation (BTVA) on LVR in patients with emphysema at different stage.MethodsA systematic search of database including PubMed, Embase and Cochrane library was conducted to determine all the studies about bronchoscopic thermal vapor ablation published through Dec 1, 2022. Related searching terms were “lung volume reduction”, “bronchoscopic thermal vapor ablation”, “bronchial thermal vapor ablation” “BTVA” and “emphysema”, “efficacy” and”safety”. We used standardized mean difference (SMD) to analyze the summary estimates for BTVA therapy.ResultsWe retrieved 30 records through database search, and 4 trials were selected for meta-analysis, including 112 patients with emphysema. Meta-analysis of the pooled effect showed that levels of forced expiratory volume in 1 s (FEV1), residual volume (RV), total lung capacity (TLC), 6-min walk distance (6MWD) and St George’s Respiratory Questionnaire (SGRQ) were significantly improved in patients with emphysema following BTVA treatment between 6 months vs. baseline. Additionally, no significant changes in FEV1, RV, TLC and SGRQ occurred from 3 to 6 months of follow-up except for 6MWD. The magnitude of benefit was higher at 3 months compared to 6 months. The most common complications at 6 months were treatment-related chronic obstructive pulmonary disease (COPD) exacerbations (RR: 12.49; 95% CI: 3.06 to 50.99; p < 0.001) and pneumonia (RR: 9.49; 95% CI: 2.27 to 39.69; p < 0.001).ConclusionsOur meta-analysis provided clinically relevant information about the impact and safety of BTVA on predominantly upper lobe emphysema. Particularly, short-term significant improvement of lung function and quality of life occurred especially within the initial 3 months. Further large-scale, well-designed long-term interventional investigations are needed to clarify this issue.

Efficacy of bronchoscopic thermal vapor ablation in patients with heterogeneous emphysema and lobar quantification by three-dimensional ventilation/perfusion single-photon emission computed tomography/computed tomography: a prospective pilot study from China.

Efficacy of bronchoscopic thermal vapor ablation in patients with heterogeneous emphysema and lobar quantification by three-dimensional ventilation/perfusion single-photon emission computed tomography/computed tomography: a prospective pilot study from China.

Bronchoscopic lung volume reduction procedures for emphysema: A network meta-analysis.

Bronchoscopic lung volume reduction (BLVR) offers alternative novel treatments for patients with emphysema. Comprehensive evidence for comparing different BLVR remains unclear. To estimate the effects of different BLVR on patients with emphysema. PubMed, EMBASE, Cochrane Library, and Web of Science databases from January 2001 to August 2017 were searched. Randomized clinical trials evaluated effects of BLVR on patients with emphysema. The relevant information was extracted from the published reports with a predefined data extraction sheet, and the risk of bias was assessed with the Cochrane risk of bias tools. Pair-wise metaanalyses were made using the random-effects model. A random-effects network meta-analysis was applied within a Bayesian framework. The quality of evidence contributing to primary outcomes was assessed using the GRADE framework. 13 trials were deemed eligible, including 1993 participants. The quality of evidence was rated as moderate in most comparisons. Medical care (MC)was associated with the lowest adverse events compared with intrabronchial valve (IBV)(-2.5,[-4.70 to -0.29]), endobronchial valve (EBV) (-1.73, [-2.37 to -1.09]), lung volume reduction coils (LVRC) (-0.76, [-1.24 to -0.28]), emphysematous lung sealant (ELS) (-1.53, [-2.66 to -0.39]), and airway bypass(-1.57, [-3.74 to 0.61]). Adverse events in LVRC were lower compared with ELS (-0.77,[-2.00 to 0.47]). Bronchoscopic thermal vapor ablation (BTVA) showed significant improvement in FEV1 compared with MC (0.99, [0.37 to 1.62]), IBV (1.25, [0.25 to 2.25]), and LVRC (0.72, [0.03 to 1.40] ). Six minute walking distance (6 MWD) in ELS was significantly improved compared with other four BLVR, sham control, and MC (-1.96 to 1.99). Interestingly, MC showed less improvement in FEV1 and 6MWDcompared with EBV (-0.45, [-0.69 to -0.20] and -0.39, [-0.71 to -0.07], respectively). The mortality in MC and EBV was lower compared with LVRC alone (-0.38, [-1.16 to 0.41] and -0.50, [-1.68 to 0.68], respectively). BTVA and EBV led to significant changes in St George's respiratory questionnaire (SGRQ) compared with MC alone (-0.74, [-1.43 to -0.05] and 0.44, [0.11 to 0.78], respectively). BLVR offered a clear advantage for patients with emphysema. EBV had noticeable beneficial effects on the improvement of forced expiratory volume 1, 6MWD and SGRQ, and was associated with lower mortality compared with MC in different strategies of BLVR.

Bronchoscopic interventions for emphysema: Current status.

Chronic obstructive pulmonary disease is a prevalent and progressive disease. The recently developed bronchoscopic lung volume reduction (BLVR) techniques offer personalized therapeutic options in subgroups of patients with severe emphysema. Endobronchial and intrabronchial valves (EBV/IBV) achieve lung volume reduction by lobar atelectasis. The lung volume reduction coils (LVRCs) and bronchoscopic thermal vapor ablation (BTVA) induce tissue compression, either mechanically or through inflammatory processes. While the effects of EBV/IBV are reversible by removing the implants, the effects of LVRC are partially reversible and that of BTVA is irreversible. The presence of interlobar collateral ventilation (CV) impacts on EBV/IBV treatment outcome due to its mechanism of action. Therefore, using radiological and endoscopic techniques to assess CV has a vital importance. Current evidence of BLVR demonstrates acceptable safety and short-term clinical efficacy. However, head-to-head trials are lacking, and further research is needed to establish long-term clinical benefit, durability, and cost-effectiveness of these techniques.

Bronchoscopic Lung Volume Reduction in Patients with Severe Emphysema.

Bronchoscopic lung volume reduction (BLVR) is a minimally invasive procedure for patients with symptomatic severe emphysema who may not be candidates for surgical lung volume reduction. BLVR has been shown to improve both functional and clinical outcomes with a relatively low risk of severe complications. Any potential candidate to BLVR should be on optimal pharmacological and nonpharmacological treatment. Radiographic and pulmonary function testing provide key data to help identify potential BLVR candidates. A variety of BLVR techniques have been published with different associated benefits and risks. Current strategies include either blocking procedures such as endobronchial valves and intrabronchial valves or nonblocking procedures such as endobronchial coils and bronchoscopic thermal vapor ablation. The aim of this review is to describe current options of BLVR including their efficacy and safety based on available data.

Thermic and chemical procedures for bronchoscopic lung volume reduction.

In the last 14 years several endoscopic procedures have been developed to offer patients with advanced chronic obstructive pulmonary disease (COPD) and emphysema further therapeutic options, complementary to a medical treatment. In addition to the established valve implantation, new approaches have been available since 2009. These procedures include bronchoscopic thermal vapor ablation (BTVA) and polymeric lung volume reduction. Both therapies are independent of collateral ventilation (CV), are irreversible and can be used on segmental (BTVA) and sub-segmental level [polymeric lung volume reduction (PLVR)], in contrast to valve therapy. The intention is to induce a local inflammation with a following fibrosis and shrinkage and thus a volume reduction in the treated lung areas. Currently, only patients with predominant upper-lobe emphysema are treated. An improvement of lung function, exercise capacity and quality of life could be proved in RCTs for BTVA as well as for PLVR. However, the data for PLVR is very limited and has recently been available only in studies. Furthermore, the risk profile is unfavourable with a high number of adverse respiratory events. While BTVA is an established new approach, the PLVR requires re-evaluation regarding materials, predictive factors, safety profile and dosage.

Bronchoscopic Lung Volume Reduction Procedures for Emphysema: A Network Meta-Analysis

Importance: Bronchoscopic lung volume reduction (BLVR) offers alternative novel treatments for patients with emphysema. Comprehensive evidence for comparing different BLVR remains unclear. Objective: To estimate the effects of different BLVR on patients with emphysema. DataSources: PubMed, EMBASE, Cochrane Library, and Web of Science databases from January 2001 to August 2017were searched. Study Selection: Randomized clinical trials (RCT) evaluated effects of BLVR on patients with emphysema. Data Extraction and Synthesis: The relevant information was extracted from the published reports with a predefined data extraction sheet, and the risk of bias was assessed with the Cochrane risk of bias tools. Main Outcomes and Measures: Pair-wise meta-analyses were made using the random-effects model. A random-effects network meta-analysis was applied within a Bayesian framework. The quality of evidence contributing to each network estimate was assessed using the GRADE framework. Results: 13 trials were deemed eligible, including 1993 participants. The quality of evidence was rated as moderate in most comparisons. Medical care (MC)was associated with the lowest adverse events compared with intra-bronchial valve (IBV)(-2.5,[-4.70 to -0.29]), endobronchial valve (EBV) (-1.73, [-2.37 to -1.09]), lung volume reduction coils (LVRC) (-0.76, [-1.24 to -0.28]), emphysematous lung sealant (ELS) (-1.53, [-2.66 to -0.39]), and airway bypass(-1.57, [-3.74 to 0.61]).Adverse events in LVRC were lower compared with ELS (-0.77,[-2.00 to 0.47]).Bronchoscopic thermal vapor ablation (BTVA) showed significant improvement inFEV1 compared with MC (0.99, [0.37 to 1.62]), IBV (1.25, [0.25 to 2.25]), and LVRC (0.72,[0.03 to 1.40]).6 MWT in ELS was significantly improved compared with other four BLVR, sham control, and MC (-1.96 to 1.99).Interestingly, MC showed less improvement in FEV1 and 6 MWT compared with EBV (-0.45, [-0.69 to -0.20] and -0.39, [-0.71 to -0.07], respectively).The mortality in MC and EBV was lower compared with LVRC alone (-0.38, [-1.16 to 0*41] and -0.50, [-1.68 to 0*68], respectively). BTVA and EBV led to significant changes in SGRQ compared with MC alone (-0.74, [-1.43 to -0.05] and 0.44, [0.11 to 0.78], respectively). Conclusions and Relevance: BLVR offered a clear advantage for patients with emphysema. EBV had noticeable beneficial effects on the improvement of FEV1, 6MWTand SGRQ, and was associated with lower mortality compared with MC in different strategies of BLVR. Funding: This project was supported by National major research program on Natural Science of China (91542164). Competing interests: The authors declare that they have no competing financial interests. Ethics Approval Statement: ??

Interventional pulmonology in chronic obstructive pulmonary disease.

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. 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. 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.

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.

Endoscopic bronchial valve treatment: patient selection and special considerations.

As well as lung volume reduction surgery, different minimally invasive endoscopic techniques are available to achieve lung volume reduction in patients with severe emphysema and significant hyperinflation. Lung function parameters and comorbidities of the patient, as well as the extent and distribution of the emphysema are factors to be considered when choosing the patient and the intervention. Endoscopic bronchial valve placement with complete occlusion of one lobe in patients with heterogeneous emphysema is the preferred technique because of its reversibility. The presence of high interlobar collateral ventilation will hinder successful treatment; therefore, endoscopic coil placement, polymeric lung volume reduction, or bronchoscopic thermal vapor ablation as well as lung volume reduction surgery can be used for treating patients with incomplete fissures. The effect of endoscopic lung volume reduction in patients with a homogeneous distribution of emphysema is still unclear and this subgroup should be treated only in clinical trials. Precise patient selection is necessary for interventions and to improve the outcome and reduce the risk and possible complications. Therefore, the patients should be discussed in a multidisciplinary approach prior to determining the most appropriate treatment for lung volume reduction.

Endoscopic volume reduction in COPD- a critical review.

Chronic obstructive pulmonary disease (COPD) is common in Germany, with a prevalence of 13.2%. The available treatments are exclusively symptomatic, except for lung transplantation, from which no more than a few patients can benefit. Over the past decade, endoscopic lung volume reduction (ELVR) has broadened the therapeutic spectrum for patients with advanced pulmonary emphysema. We review pertinent publications that were retrieved from Pubmed using the search terms "endoscopic lung volume reduction," "endobronchial valves," "endobronchial coil," and "bronchoscopic thermal vapor ablation," along with current data from the annual meeting of the German Respiratory Society (Deutsche Gesellschaft für Pneumologie). ELVR is now performed with three different techniques. Endoscopic valve implantation has been studied in three randomized controlled trials (RCTs) and several noncontrolled trials, which have shown a benefit from valve therapy particularly for patients who have only a small amount of interlobar collateral ventilation or none at all. A reduction of lobar lung volume by 56-80% was found, in association with a significant improvement of lung function (a 16-26% increase of forced expiratory volume in one second [FEV1]). The main complication of valve therapy is pneumothorax, which arises in up to 23% of cases. Coil implantation has been studied to date in only a single RCT, which revealed a significant improvement in quality of life as the primary endpoint (St. George´s Respiratory Questionnaire [SGRQ]: -8 points). Bronchoscopic thermoablation has been studied only in noncontrolled intervention trials; in patients with emphysema mainly affecting the upper lobes, it has been found to reduce lobar volume by an average of 48%. Endoscopic lung volume reduction has broadened the therapeutic spectrum for selected patients with advanced pulmonary emphysema. Further prospective trials are needed to evaluate the benefits, risks, and long-term effects of the available techniques for ELVR.

Technology update: bronchoscopic thermal vapor ablation for managing severe emphysema.

Bronchoscopic thermal vapor ablation (BTVA) is an endoscopic lung volume reduction therapy that presents an effective treatment approach in patients with severe upper lobe-predominant emphysema. By instillation of heated water vapor, an inflammatory reaction is induced, leading to fibrosis and scarring of the lung parenchyma, resulting in lobar volume reduction. Clinical single-arm trials demonstrated great outcomes, with significant improvement of lung function, exercise capacity, and quality of life. As the BTVA-induced local inflammatory response that seems to be essential for the desired lobar volume reduction can be associated with transient clinical worsening, strict monitoring of the patients is required. In future, the balance between efficacy and safety will constitute a major challenge. This review summarizes the BTVA procedure, the mechanism of action, and the results of the clinical trials, including the efficacy and safety data.

Endoscopic Lung Volume Reduction. A European Perspective

Endoscopic lung volume reduction (ELVR) offers a novel therapeutic approach for patients with severe pulmonary emphysema. In Europe, several types of ELVR are available. The choice of ELVR technique depends both on the distribution of emphysema and the presence or absence of interlobar collateral ventilation (CV). For this reason, accurate patient selection is crucial. Bronchial valve implantation is the technique that has been most widely studied and represents an effective treatment option for patients with severe heterogeneous upper- or lower-lobe-predominant emphysema. Lobar occlusion and low interlobar CV are predictive factors for positive outcomes. Lung volume reduction coil implantation is an effective option for patients with upper- and lower-lobe-predominant emphysema, and the efficacy is not influenced by CV; however, the technique should be regarded as mainly irreversible. Polymeric lung volume reduction relies on irreversible scarring and fibrosis and is especially effective in patients with chronic obstructive pulmonary disease classified as Global Initiative for Chronic Obstructive Lung Disease stage III; it also offers benefits to patients with upper-lobe-predominant emphysema and those with homogeneous emphysema. Like polymeric lung volume reduction, bronchoscopic thermal vapor ablation is also not influenced by CV and represents a good option for patients with upper-lobe-predominant emphysema. Exhale airway stents for emphysema--"airway bypass"--appeared to be a promising technique but proved ineffective in randomized clinical trials, likely in part due to long-term occlusion of the drug-eluting stents. Although European physicians are able to choose from a host of approved bronchoscopic interventions for emphysema, future studies for techniques in use are needed to further clarify patient selection criteria.

The Localized Inflammatory Response to Bronchoscopic Thermal Vapor Ablation

Background: Bronchoscopic thermal vapor ablation (BTVA) reduces lung volumes in emphysema patients by inducing a localized inflammatory response (LIR) leading to a healing process of fibrosis, but may also increase symptoms. Objectives: We sought to evaluate whether the clinical manifestation of LIR correlated with patient outcome. Methods: Respiratory adverse events and inflammatory markers were analyzed from a multicenter trial of BTVA in patients with upper-lobe-predominant emphysema. End points including changes in forced expiratory flow (FEV₁), lobar volume, St. George's Respiratory Questionnaire (SGRQ), modified Medical Research Council (mMRC) and 6-minute-walk distance (6-MWD) were analyzed according to the presence or absence of a respiratory adverse event requiring treatment with an antibiotic or steroid. Results: Forty-four patients received BTVA. Increases of inflammatory markers were observed with a peak between the second and fourth week. Eighteen respiratory adverse events occurred in 16 patients within 30 days of BTVA, requiring antibiotics and/or steroids. These patients had significantly greater lobar volume reduction (65.3 vs. 33.4%, p = 0.007) and a change in residual volume at 12 months (-933 vs. 13 ml, p < 0.001) associated with a greater improvement of exercise capacity and health-related quality of life than patients without respiratory adverse events. Conclusion: Patients with more prominent respiratory symptoms in the first 30 days following BTVA experience greater efficacy. The clinical manifestations of the LIR are predictive of long-term clinical benefits.

Efficacy of Bronchoscopic Thermal Vapor Ablation and Lobar Fissure Completeness in Patients with Heterogeneous Emphysema

Background: Bronchoscopic thermal vapor ablation (BTVA) ablates emphysematous tissue through a localized inflammatory response followed by contractive fibrosis and tissue shrinkage leading to lung volume reduction that should not be influenced by collateral ventilation. Objectives: To determine the correlation of clinical data from a trial of BTVA with fissure integrity visually assessed by computed tomography (CT). Methods: We conducted a single-arm study of patients with upper lobe-predominant emphysema (n = 44). Patients received BTVA either to the right upper lobe or left upper lobe, excluding the lingula. Primary efficacy outcomes were forced expiratory volume in 1 s (FEV₁) and St. George’s Respiratory Questionnaire (SGRQ) at 6 months. Lobar volume reduction from CT was another efficacy outcome measurement. The fissure of the treated lobe was analyzed visually on preinterventional CT. Incompleteness of the small fissure, the upper half of the right large fissure and the whole left large fissure were estimated visually in 5% increments, and the relative amount of fissure incompleteness was calculated. Pearson correlation coefficients were calculated for the association between fissure incompleteness and change in efficacy outcomes (baseline to 6 months) of BTVA. Results: A total of 38 out of 44 patients (86%) had incompleteness in the relevant fissure. Calculated relevant fissure incompleteness was a mean of 13% of fissure integrity (range 0–63). Correlation coefficients for the association of incompleteness with outcomes were as follows: FEV₁ = 0.17; lung volume reduction = –0.27; SGRQ score = –0.10; 6-min walk distance = 0.0; residual volume (RV) = –0.18, and RV/total lung capacity = –0.14. Conclusions: Lobar fissure integrity has no or minimal influence on BTVA-induced lung volume reduction and improvements in clinical outcomes.

Bronchoscopic thermal vapor ablation in a canine model of emphysema

Clinical studies indicate the potential of bronchoscopic thermal vapor ablation to result in clinically relevant improvements in severe chronic obstructive pulmonary disease patients with upper lobe-predominant emphysema. However, the mechanisms by which vapor ablation results in lung volume reduction are not fully known. This study determined the 3-month safety and efficacy of vapor ablation in a canine model of emphysema and described the histopathological changes in the lung. The cranial lobes of papain-exposed dogs were treated with a vapor dose of ten calories per gram of lung tissue (n = 8) or were sham treated (n = 3). Safety was monitored peri- and postoperatively for 3 months. Animals were then sacrificed, estimates of lung volume reduction performed, and the lungs processed for histology. Vapor ablation was associated with an average of 20% volume reduction of the treated lobes and an absence of serious adverse events. The amount of lobar volume reduction was correlated with the amount of fibrosis and atelectasis in the treated lobe. Bronchoscopic thermal vapor ablation at a dose of 10 cal/g results in lobar volume reduction associated with remodeling of the targeted tissue characterized by mature collagen formation in the absence of major adverse events.

A Feasibility and Safety Study of Bronchoscopic Thermal Vapor Ablation: A Novel Emphysema Therapy

This study reports the feasibility and safety of novel second-generation bronchoscopic lung volume reduction (LVR) technology, independent of collateral ventilation. Eleven patients with severe heterogeneous emphysema underwent unilateral bronchoscopic application of vapor thermal energy (mean 4.9 cal/g alveolar tissue; range, 3 to 7.5) with bronchial thermal vapor ablation (BTVA) aiming to induce a controlled inflammatory airway and parenchymal response with resultant LVR. Nine women and 2 men, with a mean age of 61 years, forced expiratory volume in 1 second (FEV(1)) of 0.77 +/- 0.17 L (32% predicted), residual volume (RV) of 4.1 +/- 0.9 L (219% predicted), and gas transfer of 7.8 +/- 2.2 (34% predicted), underwent unilateral upper lobe treatments. Serious adverse events in 5 included probable bacterial pneumonia and exacerbations of airways disease in 2. Although no important FEV(1) or RV changes occurred during 6 months of follow-up, gas transfer improved, 16% to 9.0% +/- 2.1% (38% predicted), the Medical Research Council Dyspnoea Score improved from 2.6 to 2.1, and the St. George Respiratory Questionnaire Total Score improved from 64.4 at baseline to 49.1. These preliminary data on unilateral BTVA therapy confirm feasibility, an acceptable safety profile, and the potential for efficacy.