From the Guidelines
Zephyr valves are recommended for patients with severe emphysema who meet specific criteria, including hyperinflation, limited airflow, and symptomatic disease despite optimal medical therapy. The criteria for Zephyr valve placement include:
- Hyperinflation with a residual volume greater than 175% of predicted
- Limited airflow with FEV1 between 15-45% of predicted
- Symptomatic disease despite optimal medical therapy, including bronchodilators, inhaled steroids, and pulmonary rehabilitation
- Intact fissures (>90% completeness) on CT scan
- Heterogeneous emphysema with a target lobe that can be completely occluded
- Non-smokers or those who have quit smoking for at least 4 months Exclusion criteria include severe pulmonary hypertension, history of frequent respiratory infections, significant bronchiectasis, large bullae, prior lung surgery, or active lung infections, as reported in the Global Strategy for the Diagnosis, Management, and Prevention of Chronic Obstructive Lung Disease 2017 report 1. The Zephyr valve procedure works by blocking airflow to diseased portions of the lung, allowing healthier regions to expand and function better, reducing hyperinflation and improving breathing mechanics, with studies showing statistically significant improvements in FEV1 and 6-minute-walk distance compared with control therapy at 6 months postintervention 1.
From the Research
Criteria for Zephyr Valves
The criteria for Zephyr valves include:
- Hyperinflation with a residual volume >175% of predicted 2
- Forced expiratory volume <50% of predicted 2
- A 6-min walking distance >100 m 2
- Patients with repeated infectious complications, severe bronchiectasis, and those with unstable cardiovascular comorbidities should be excluded from EBV treatment 2
Patient Selection
Patient selection is crucial for the success of Zephyr valve treatment. The following factors should be considered:
- Presence of collateral ventilation 3
- Heterogeneous or homogeneous emphysema 3, 4
- Age and overall health of the patient 4
Procedure and Complications
The procedure for Zephyr valve placement can be performed with either conscious sedation or general anesthesia and positive pressure mechanical ventilation 2. Complications such as pneumothorax are common and typically occur in the first 2 days following treatment 2, 5, 6. Management of complications is crucial to minimize adverse events 4, 6.
Efficacy and Safety
The efficacy and safety of Zephyr valves have been demonstrated in several studies:
- Improvement in forced expiratory volume, 6-min walking distance, and quality of life 3, 5, 6
- Significant reduction in residual volume 3, 6
- Comparable improvements in lung function and quality of life compared to other valve types 5
- Acceptable risk profile with combined implantation of Zephyr and Spiration valves 6