Endobronchial valves for severe emphysema

Abstract

The results of the randomised controlled trials investigating the bronchoscopic lung volume reduction treatment using endobronchial valves (EBV) are promising, and have led to their inclusion in treatment guidelines, US Food and Drug Administration approval and inclusion in routine care in an increasing number of countries. The one-way valve treatment has advanced and is now a regular treatment option. However, this new phase will lead to new challenges in terms of implementation. We believe that key issues in future research concern advanced patient selection, improved methods for target lobe selection, increased knowledge on the predictive risk of a pneumothorax, positioning of pulmonary rehabilitation in conjunction with the EBV treatment, the positioning of lung volume reduction surgery versus EBV treatment, and the long-term efficacy, adverse events, impact on exacerbations and hospitalisations, costs and survival. Hopefully, the increasing number of patients treated, the setup of (inter)national registries and future research efforts will further optimise all aspects of this treatment.

FIGURE 1

Endobronchial valve (EBV) treatment for emphysema, summary of treatment selection and outcome. The key selection criteria for success (do) and restraints for treatment (don't) are shown. The criteria for success (do) are: severe emphysema; complete interlobar fissure (no collateral flow); severe hyperinflation (residual volume (RV) >175% pred, RV/total lung capacity (TLC) >55%); symptomatic; non-smoking; on optimal treatment; and stable condition. The criteria for restraints (don't) are: presence of a suspect nodule; pleural pathology; severe bronchiectasis; incomplete fissure; fibrosis; severe cardiac comorbidity (i.e. pulmonary arterial hypertension (PAH), congestive heart failure (CHF) and coronary artery disease (CAD)); infectious lung disease; chronic bronchitis or asthma; prior lobectomy or lung volume reduction surgery (LVRS) on treatment side; hypercapnia/hypoxaemia; and immunocompromised. The figure also shows the mean responder rates and percentage of risk related to EBV treatment from the four published randomised controlled trials. Responder rates are the percentage of patients who reached the earlier established minimal important difference: forced expiratory volume in 1s (FEV₁) ≥12% (STELVIO ≥10%), RV ≥430 mL (LIBERATE ≥310 mL), 6-min walk distance (6MWD) ≥25 m, St George's Respiratory Questionnaire (SGRQ) ≥4 points. ^#: modified Medical Research Council scale ≥2 or 100 m<6MWD<500 m; ^¶: partial pressure of carbon dioxide >60 mmHg/partial pressure of oxygen <45 mmHg.