Pulmonary fissure integrity and collateral ventilation in COPD patients

Purpose: To investigate whether the integrity (completeness) of pulmonary fissures affects pulmonary function in patients with chronic obstructive pulmonary disease (COPD). Materials and Methods: A dataset consisting of 573 CT exams acquired on different subjects was collected from a COPD study. According to the global initiative for chronic obstructive lung disease (GOLD) criteria, these subjects (examinations) were classified into five different subgroups, namely non-COPD (222 subjects), GOLD-I (83 subjects), GOLD-II (141 subjects), GOLD-III (63 subjects), and GOLD-IV (64 subjects), in terms of disease severity. An available computer tool was used to aid in an objective and efficient quantification of fissure integrity. The correlations between fissure integrity, and pulmonary functions (e.g., FEV1, and FEV1/FVC) and COPD severity were assessed using Pearson and Spearman's correlation coefficients, respectively. Results: For the five sub-groups ranging from non-COPD to GOLD-IV, the average integrities of the right oblique fissure (ROF) were 81.8%, 82.4%, 81.8%, 82.8%, and 80.2%, respectively; the average integrities of the right horizontal fissure (RHF) were 62.6%, 61.8%, 62.1%, 62.2%, and 62.3%, respectively; the average integrities of the left oblique fissure (LOF) were 82.0%, 83.2%, 81.7%, 82.0%, and 78.4%, respectively; and the average integrities of all fissures in the entire lung were 78.0%, 78.6%, 78.1%, 78.5%, and 76.4%, respectively. Their Pearson correlation coefficients with FEV1 and FE1/FVC range from 0.027 to 0.248 with p values larger than 0.05. Their Spearman correlation coefficients with COPD severity except GOLD-IV range from -0.013 to -0.073 with p values larger than 0.08. Conclusion: There is no significant difference in fissure integrity for patients with different levels of disease severity, suggesting that the development of COPD does not change the completeness of pulmonary fissures and incomplete fissures alone may not contribute to the collateral ventilation. © 2014 Pu et al

Endobronchial coils for emphysema:Dual mechanism of action on lobar residual volume reduction

BACKGROUND AND OBJECTIVE: The RENEW trial demonstrated that bronchoscopic lung volume reduction using endobronchial coils improves quality of life, pulmonary function and exercise performance. In this post hoc analysis of RENEW, we examine the mechanism of action of endobronchial coils that drives improvement in clinical outcomes. METHODS: A total of 78 patients from the RENEW coil-treated group who were treated in one or both lobes that were deemed as the most destroyed were included in this retrospective analysis. Expiratory and inspiratory HRCT scans were used to assess lobar volume change from baseline to 12 months post coil treatment in treated and untreated lobes. RESULTS: Reduction in lobar RV in treated lobes was significantly associated with favourable clinical improvement. Independent predictor of the change in RV and FEV1 was the change in lobar RV reduction in the treated lobes and for change in 6MWD the absence of cardiac disease and the change in SGRQ, while the independent predictor of change in SGRQ was the change in 6MWD. CONCLUSION: Our results suggest that residual lobar volume reduction in treated lobes measured by QCT is the driving mechanism of action of endobronchial coils leading to positive clinical outcomes. However, the improvement in exercise capacity and quality of life seems to be affected by the presence of cardiac disease

New Spirometry Indices for Detecting Mild Airflow Obstruction.

The diagnosis of chronic obstructive pulmonary disease (COPD) relies on demonstration of airflow obstruction. Traditional spirometric indices miss a number of subjects with respiratory symptoms or structural lung disease on imaging. We hypothesized that utilizing all data points on the expiratory spirometry curves to assess their shape will improve detection of mild airflow obstruction and structural lung disease. We analyzed spirometry data of 8307 participants enrolled in the COPDGene study, and derived metrics of airflow obstruction based on the shape on the volume-time (Parameter D), and flow-volume curves (Transition Point and Transition Distance). We tested associations of these parameters with CT measures of lung disease, respiratory morbidity, and mortality using regression analyses. There were significant correlations between FEV1/FVC with Parameter D (r = -0.83; p < 0.001), Transition Point (r = 0.69; p < 0.001), and Transition Distance (r = 0.50; p < 0.001). All metrics had significant associations with emphysema, small airway disease, dyspnea, and respiratory-quality of life (p < 0.001). The highest quartile for Parameter D was independently associated with all-cause mortality (adjusted HR 3.22,95% CI 2.42-4.27; p < 0.001) but a substantial number of participants in the highest quartile were categorized as GOLD 0 and 1 by traditional criteria (1.8% and 33.7%). Parameter D identified an additional 9.5% of participants with mild or non-recognized disease as abnormal with greater burden of structural lung disease compared with controls. The data points on the flow-volume and volume-time curves can be used to derive indices of airflow obstruction that identify additional subjects with disease who are deemed to be normal by traditional criteria

Impact of emphysema heterogeneity on pulmonary function

Results: The majority (128/160) of the subjects with COPD had a heterogeneity greater than zero. After adjusting for age, gender, smoking history, and extent of emphysema, heterogeneity in depicted disease in upper lobe dominant cases was positively associated with pulmonary function measures, such as FEV1 Predicted (p<.001) and FEV1/FVC (p<.001), as well as disease severity (p<0.05). We found a negative association between HI% , RV/TLC (p<0.001), and DLco% (albeit not a statistically significant one, p = 0.06) in this group of patients

Unilateral thoracoscopic surgical approach for diffuse emphysema

AbstractWe evaluated the use of a lateral thoracoscopic approach for lung reduction surgery in patients with diffuse emphysema. Sixty-seven patients with a mean age of 61.9 years underwent operation. Operative side was determined by preoperative imaging. The procedures were laser ablation in 10 patients and stapler resection in 57 patients. Ten patients, including six of the 10 patients in the laser-only group had poor outcome (death or hospitalization longer than 30 days), leading us to abandon the laser technique. Of the remaining 57 patients undergoing primary stapled resection, duration of chest tube placement averaged 13 days (range 3 to 53 days) with a mean hospital stay of 17 days (range 6 to 99 days). Seven patients required ventilation for longer than 72 hours, six patients underwent conversion of the procedure to open thoracotomy, four patients acquired arrhythmias, and three patients were treated for empyema. There was one early death (1.7%), from cardiopulmonary failure. Forty patients returned for 3-month evaluation. Significant ( p < 0.0001) improvements were seen in forced vital capacity (2.69 L after vs 2.26 L before) and forced expiration volume in 1 second (1.04 L after vs 0.82 L before), with 25 of 40 patients (63%) showing an improvement of more than 20%. Lung volume measures, in particular residual volume, fell significantly. Arterial blood gas analysis revealed that carbon dioxide tension fell significantly in patients with preoperative hypercapnia (carbon dioxide tension >45 mm Hg, p = 0.018). Six-minute walk test results improved (894 feet after vs 784 feet before, p = 0.002), and symptomatic benefit was confirmed by significant improvement in the dyspnea index. The combination of both hypercapnia and reduced single-breath diffusing capacity for carbon monoxide was significantly more frequent ( p = 0.0026) and was 86% specific (5 of 6 patients) in predicting serious postoperative risk. We conclude that the lateral thoracoscopic surgical approach to diffuse emphysema offers significant improvement in pulmonary mechanics and functional impairment. Patients with a combination of hypercapnia and reduced single-breath diffusing capacity for carbon monoxide should not be considered for this procedure because of significant perioperative risk. (J THORAC CARDIOVASC SURG 1996;111:308-16

Design for a multicenter, randomized, sham-controlled study to evaluate safety and efficacy after treatment with the Nuvaira (R) lung denervation system in subjects with chronic obstructive pulmonary disease (AIRFLOW-3)

Background Targeted lung denervation (TLD) is a bronchoscopically delivered ablation therapy that selectively interrupts pulmonary parasympathetic nerve signaling. The procedure has the potential to alter airway smooth muscle tone and reactivity, decrease mucous secretion, and reduce airway inflammation and reflex airway hyperresponsiveness. Secondary outcome analysis of a previous randomized, sham-controlled trial showed a reduction in moderate-to-severe exacerbations in patients with COPD after TLD treatment. A pivotal trial, AIRFLOW-3 has been designed to evaluate the safety and efficacy of TLD combined with optimal medical therapy to reduce moderate or severe exacerbations throughout 1 year, compared with optimal medical therapy alone. Methods The study design is a multicenter, randomized, full sham bronchoscopy controlled, double-blind trial that will enroll 400 patients (1:1 randomization). Key inclusion criteria are FEV1/FVC < 0.7, FEV1 30 to 60% of predicted, post-bronchodilator, ≥ 2 moderate or 1 severe COPD exacerbations in the prior year, and COPD assessment test (CAT) ≥ 10. Primary objective will be the comparison of moderate or severe COPD exacerbations through 12 months of TLD therapy with optimal medical therapy versus optimal medical therapy alone. The sham group will be allowed to cross over at 1 year. Patients will be followed for up to 5 years. Discussion The multicenter, randomized, full sham bronchoscopy controlled, double-blind AIRFLOW-3 trial will evaluate the efficacy of TLD to reduce moderate or severe COPD exacerbations beyond optimal medical therapy alone. The target population are patients with COPD, who suffer persistent symptoms and exacerbations despite optimal treatment, defining an unmet medical need requiring novel therapeutic solutions. This trial is registered at clinicaltrials.gov: NCT03639051

Bronchoscopic Lung Volume Reduction Coil Treatment for Severe Emphysema:A Systematic Review and Meta-Analysis of Individual Participant Data

BACKGROUND: Lung volume reduction coil (LVR-coil) treatment provides a minimally invasive treatment option for severe emphysema patients which has been studied in multiple clinical trials. OBJECTIVES: The aim of the study was to assess the effect of LVR-coil treatment on pulmonary function, quality of life, and exercise capacity using individual participant data. METHOD: PubMed, Web of Science, and EMBASE were searched until May 17, 2021. Prospective single-arm and randomized controlled trials that evaluated the effect of LVR-coil treatment on forced expiratory volume in 1 s (FEV1), residual volume (RV), St. George Respiratory Questionnaire (SGRQ) total score, and/or 6-min walk distance (6MWD) and were registered in an official clinical trial database were eligible for inclusion. Individual patient data were requested, and a linear mixed effects model was used to calculate overall treatment effects. RESULTS: Eight trials were included in the final analysis, representing 680 individual patients. LVR-coil treatment resulted in a significant improvement in FEV1 at 3- (0.09 L [95% confidence interval (95% CI): 0.06-0.12]) and 6-month follow-up (0.07 L [95% CI: 0.03-0.10]), a significant reduction in RV at 3- (-0.45L [95% CI: -0.62 to -0.28]), 6- (-0.33L [95% CI: -0.52 to -0.14]), and 12-month follow-up (-0.36L [95% CI: -0.64 to -0.08]), a significant reduction in SGRQ total score at 3- (-12.3 points [95% CI: -15.8 to -8.8]), 6- (-10.1 points [95% CI: -12.8 to -7.3]), and 12-month follow-up (-9.8 points [95% CI: -15.0 to -4.7]) and a significant increase in 6MWD at 3-month follow-up (38 m [95% CI: 18-58]). CONCLUSIONS: LVR-coil treatment in emphysema patients results in sustained improvements in pulmonary function and quality of life and shorter lived improvements in exercise capacity. Since the owner of this LVR-coil has decided to stop the production and newer generations LVR-coils are currently being developed, these results can act as a reference for future studies and clinical guidance

HRCT characteristics of severe emphysema patients:Interobserver variability among expert readers and comparison with quantitative software

PURPOSE: For a successful bronchoscopic lung volume reduction coil treatment it is important to place the coils in the most emphysematous lobes. Therefore assessment of the lobe with greatest destruction is essential. Our aims were to investigate the level of agreement among expert reviewers of HRCT-scans in emphysema patients and the comparison with QCT (quantitative computed tomography) software. METHOD: Five experienced CT-assessors, conducted a visual assessment of the baseline HRCT-scans of emphysema patients who participated in the RENEW bronchoscopic lung volume reduction coil study. On the same HRCT-scans, a QCT analysis was performed. RESULTS: In total 134 HRCT-scans were rated by all 5 experts. All 5 CT-assessors agreed on which was the most destructed lobe in 61 % of the left lungs (k:0.459) and 60 % of the right lungs (k:0.370). The consensus of the 5 assessors matched the QCT in the left lung for 77 % of the patients (k:0.425) and in the right lung for 82 % (k:0.524). CONCLUSIONS: Our results show that the interobserver agreement between five expert CT-assessors was only fair to moderate when evaluating the most destructed lobe. CT-assessor consensus improved matching with QCT determination of lobar destruction compared to individual assessor determinations. Because some CT-features are associated with treatment outcomes and important for optimal patient selection of bronchoscopic lung volume reduction treatment, we recommend including more than one CT-reviewer and supported by QCT measurements