VENT Study
In the US VENT study, 321 patients with advanced emphysema were randomised 2:1 to receive endobronchial valves (220 patients) or standard medical care (101 patients). All patients underwent pulmonary rehabilitation and optimization of medical treatment prior to randomization.
The results of this study showed a statistically significant improvement in forced expiratory volume in one second (FEV1), 6 minute walk test (6MWT) and the St. George’s Respiratory Questionnaire (SGRQ) for the patients receiving endobronchial valve (EBV) therapy compared to the controls (Table 1)1.
Table 1 Overall US VENT results at 6 months
| EBV N=220 | |
Control N=101 | |
Between group difference in change from baseline | |
P value | ||||
| FEV1 mean absolute % change from baseline | 4.3 (1.4 to 7.2) | -2.5 (-5.4 to 0.4) | 6.8 (2.1 to 11.5) | 0.0005 | ||||||
| 6MWT median absolute % change from baseline | 2.5 (-1.1to 6.1) | -3.2 (-8.9 to 2.4) | 5.8 (0.5 to 11.2) | 0.04 | ||||||
| Mean change in score on SGRQ from baseline | -2.8 (-4.7to-1.0) | 0.6 (-1.8 to 3.0) | -3.4 (-6.7 to 0.2) | 0.04 |
It should be noted that in this study, lobar occlusion was NOT achieved in 43.9% of patients, and only 39% of patients had complete fissures, indicative of low collateral ventilation. We now know that fully occluding a target lobe that has little or no collateral ventilation is the key to achieving significant lung volume reduction and clinical response,2,3 and this helps put the VENT results in appropriate context.
In the International arm of the VENT study (EURO-VENT), patients were enrolled and treated using the same investigative protocol as that of the U.S. VENT study. The EURO-VENT data is currently awaiting publication.
EBV treatment is a minimally-invasive procedure with a lower incidence of risks and more rapid recovery than surgical lung volume reduction. Beyond the well-described procedural risks of bronchoscopy, EBV treatment is also associated with a few incremental risks, notably pneumothorax and COPD exacerbations, mostly occurring in the acute post-treatment period and resolvable with standard treatment.
The VENT Study confirmed a favorable safety profile for EBV therapy, and the primary safety endpoint was met. This positive safety profile must be further appreciated in light of the fact that procedural and treatment-related events in the acute period following treatment are compared to controls who received neither a bronchoscopy nor valve implants.
Table 2. VENT Study, MCC results, through one year, control vs. treated groups
| VENT MCCs, through 1 year | |
Control (N=87) | |
Zephyr EBV (N=214) | |
P value | ||
| All-cause mortality | 3.5% | 3.7% | 1.000 | |||||
| Pneumonia* (not distal / distal to valve) | 9.2% | 7.0% / 4.2% | — | |||||
| Massive hemoptysis | 0.0% | 0.5% | 1.000 | |||||
| Respiratory failure >24 hours | 2.3% | 2.8% | 1.000 | |||||
| Pneumothorax | 2.3% | 4.7% | 0.5192 | |||||
| Empyema | 0.0% | 0.0% | 1.000 |
A values are mean±SD [95% confidence interval bounds] unless noted
* Only distal pneumonia was included in the VENT MCC; however since pneumonia distal to the valve is not possible in the control cohort, rates for all pneumonia are included in this table.
The VENT data showed that the MCC for EBV treated (4.7%) and control (4.6%) groups were statistically similar in the 6 month to one year time period. In the 6-month to 1-year window, no patients had empyema or massive hemoptysis, and respiratory failure rates were similar (1.2% control vs. 0.9% EBV). Pneumothorax rates were 0.0% for control vs. only 0.5% EBV.
The European responder data confirmed the findings of the U.S. responder data – EBV therapy significantly improves lung function, exercise capacity and quality of life, with outstanding outcomes when higher lung volume reduction is achieved.4
The lesson is clear: a successful EBV treatment plan should have the goal of achieving as much lung volume reduction as possible, given a specific patient’s anatomy. Using the Chartis system to assess a patient’s target lobes is an essential planning step that enables physicians to make data-driven treatment decisions, and achieve optimal outcomes for each patient.
Pooling data from both the US and EURO-VENT studies, an analysis of the subgroup of patients in whom the TLVR was greater than 55% showed significant and substantial increased improvements in clinical parameters4 (Table 3).
Table 3. Super-responders at 6 months (pooled data):
EBV patients who achieved >55% TLVR N=40A
| Mean TLVR (%) | 86.5% | ||
| Change in FEV1 from baseline at 6 months (%) | 29.5% | ||
| Change in 6MWT from baseline at 6 months (%) | 23.5% | ||
| Change in SGRQ from baseline at 6 months (points) | -7.3 (N=26) |
A values are means
- Sciurba F, et al. A Randomized Study of Endobronchial Valves for Advanced Emphysema. New England Journal of Medicine, 2010; 363:1233-1244.
- Gompelmann D, Eberhardt R, Ernst A, et al. Predicting Atelectasis Using Collateral Ventilation Assessment prior to Endobronchial Lung Volume Reduction – A Feasibility Study. Respiration 2010;80:419-425; doi: 10.1159/000319441.
- Use of Chartis® Pulmonary Assessment System to Optimize Subject Selection for Endobronchial Lung Volume Reduction (ELVR). Chartis Multi-Centre Study, data presented at ATS2011. Data on file with Pulmonx.
- Herth FJF, et al. Endoscopic Lung Volume Reduction with One-way Valves in a Large European Cohort of Emphysema Patients: A Multi-Center Prospective, Randomized, Controlled Trial, Poster Session, 2011 American Thoracic Society Meeting, Denver.
