Endobronchial Silicone Valve for Patients With Emphysema

Inclusion Criteria: * Clinical and radiological evidence of emphysema * Nonsmoking for 4 months prior to screening interview * BMI less than 35 kg/m2 * Stable on current medication regimen * Forced expiratory volume in one second (FEV1) between 15% and 45% of predicted value * Residual Volume less than 175% predicted (determined by body plethysmography) * Little or no collateral ventilation (CV-) as determined using the Chartis System Exclusion Criteria: * Had two or more hospitalizations over the last year for a COPD exacerbation * Had two or more hospitalizations over the last year for pneumonia * Had a prior lung transplant, lung volume reduction surgery, bullectomy or lobectomy * Had a heart attack or congestive heart failure within the last 6 months * Have heart arrhythmia * Is alpha-1 antitrypsin deficient