Identifying Responders and Exploring Mechanisms of Action of the Endobronchial Coil Treatment for Emphysema

Abstract

Background: So far, 3 randomized controlled trials have shown that the endobronchial treatment using coils is safe and effective. However, the more exact underlying mechanism of the treatment and best predictors of response are unknown. Objectives: The aim of the study was to gain more knowledge about the underlying physiological mechanism of the lung volume reduction coil treatment and to identify potential predictors of response to this treatment. Methods: This was a prospective nonrandomized single-center study which included patients who were bilaterally treated with coils. Patients underwent an extensive number of physical tests at baseline and 3 months after treatment. Results: Twenty-four patients (29% male, mean age 62 years, forced expiratory volume in 1 s [FEV1] 26% pred, residual volume (RV) 231% pred) were included. Three months after treatment, significant improvements were found in spirometry, static hyperinflation, air trapping, airway resistance, treated lobe RV and treated lobes air trapping measured on CT scan, exercise capacity, and quality of life. The change in RV and airway resistance was significantly associated with a change in FEV1, forced vital capacity, air trapping, maximal expiratory pressure, dynamic compliance, and dynamic hyperinflation. Predictors of treatment response at baseline were a higher RV, larger air trapping, higher emphysema score in the treated lobes, and a lower physical activity level. Conclusions: Our results confirm that emphysema patients benefit from endobronchial coil treatment. The primary mechanism of action is decreasing static hyperinflation with improvement of airway resistance which consequently changes dynamic lung mechanics. However, the right patient population needs to be selected for the treatment to be beneficial which should include patients with severe lung hyperinflation, severe air trapping, and significant emphysema in target lobes.

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

“…Nine trials were found eligible for inclusion, and all accepted to share IPD (shown in Fig. 1 ) [ 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ]. One trial was unable to supply sufficient data to identify the original study population in the supplied IPD and was therefore excluded from the meta-analysis [ 20 ].…”

“…Details on the record selection can be found in the supplement. Five trials reported outcomes at 3-month follow-up [ 14 , 16 , 18 , 21 , 22 ], four trials at 6-month follow-up [ 13 , 15 , 17 , 19 ], and three trials at 12-month follow-up after final treatment [ 15 , 17 , 18 ] (shown in Fig. 1 , and in online suppl.…”

Surgical and bronchoscopic pulmonary function-improving procedures in lung emphysema

“…The working mechanism is explained as follows: compression of the lung parenchyma reduces the lobar RV and increases airflow to untreated regions; thereby, hyperinflation may be reduced and diaphragm function may improve. By pulling together the most destroyed segments, the elastic recoil of the lung improves, ameliorating expiratory flow and air trapping [ 110 , 111 ]. This is also reflected by the beneficial effect of coil-associated opacities [ 73 , 112 ].…”

Endoscopic Options for Moderate COPD, Chronic Bronchitis, and Uncontrolled Asthma

“…Gala-Therapeutics' RheOx technology involves the delivery of a pulsed electronic field (high frequency, short-duration, nonthermal electrical fields). 21 This targeted energy delivery is intended to cause goblet cell death by disrupting cellular homeostasis, leading to processes such as osmotic swelling and apoptosis. 22 This cell death does not destroy the architectural function of the tissue, permitting subsequent regeneration of normalized epithelium and a reduction in airway mucus production.…”