A 63-year-old Chinese male with COPD was admitted to our hospital in October 2013. He was presented with a 20-year history of chronic productive cough and progressive dyspnea. The patient was an ex-smoker (40 pack-years), had suffered from secondary tuberculosis before 30 years, and had been taking salmeterol/fluticasone propionate (50/500 mug) twice daily for 2 years. Pulmonary function tests administered on admission revealed severe irreversible airflow obstruction after bronchodilator inhalation (forced expiratory volume in one second [FEV1]/forced vital capacity [FVC] =46.9%; FEV1 =0.89 L, 28.9% of predicted value) and severe hyperinflation (residual volume [RV] =5.03 L, 222% of predicted value, total lung capacity [TLC] =7.92 L, 131% of predicted value). Additional tests revealed the following: 6-min walking distance (6MWD), 144 m; St George respiratory questionnaire (SGRQ) score, 64; and Modified Medical Research Council (MMRC) dyspnea score, 4. Analysis of the blood gases at pH 7.40 revealed the following: PaO2, 65.7 mmHg and PaCO2, 42.1 mmHg.
High-resolution chest CT (HRCT) indicated heterogeneous emphysema with a marked predominance in the bilateral upper lobes and middle lobe (Figure 1A and B). The right oblique fissure was complete, and a peripheral minor defect was found on the horizontal fissure in the coronary and sagittal views; however, we calculated the integrity of horizontal fissure to be 91.6% and 91%, respectively (Figure 1C and D).
We performed a purified protein derivative test, erythrocyte sedimentation rate analysis, contrast CT, sputum smears, and cytopathology. No evidence of lung cancer or active secondary tuberculosis was present. With the patient's informed consent for BLVR, we administered 0.5 mg atropine to minimize bronchial secretion and 50 mg pethidine to reduce the cough. We performed bronchoscopy using 20 mL lidocaine as a local anesthetic and measured the CV using the Chartis system. We blocked the right upper bronchus using a balloon catheter and measured the expiratory airflow. This assessment revealed sudden stops in expiratory flow during the three breathing maneuvers that were accompanied by sharp increases in resistance, which is a common characteristic of the low-flow phenotype (Figure 1E). It was difficult to confirm whether CV was present; therefore, we measured CV in the ipsilateral lobes. Assessment of the middle lobe revealed that CV was negative or CV was positive with on/offs in expiratory flow that occurred during deeper and lower breathing maneuvers, which were signs of mini-collaterals that were open only during deeper inspirations (Figure 1F). Assessment of the right lower lobe (RLL) revealed a good signal with a gradual downward trend without CV (Figure 1G). We implanted three EBVs (Zephyr EBV 4.0; Pulmonx) in the right upper bronchus for economic reasons.
One month later, the patient exhibited limited improvements in lung function, 6MWD, and volume reduction of the RUL on HRCT (Figure 1H). We speculated that this lack of improvement might have been associated with latent CV between the RUL and RML that caused a minor leak in the horizontal fissure. Therefore, we decided to block the right middle bronchus using another EBV (Zephyr EBV 5.5).
Two weeks later, quantitative analysis of the HRCT images (Lung CAD1.2; Neusoft, Shenyang, People's Republic of China) revealed that the volume of the right lung had decreased from 3,838 to 2,935 mL, the RUL and RML had begun to shrink, the right diaphragm had become elevated, and the mediastinum had shifted to the right side (Figure 1I and J). The patient exhibited significant clinical improvement. The FEV1 increased to 1.52 L (+0.63 L) and the 6MWD increased to 216 m (+72 m); in addition, the RV decreased to 4.21 L (-16.3%), the TLC decreased to 7.10 L (-10.4%), the SGRQ score decreased to 41, and the MMRC dyspnea score decreased to 2.
The patient reported slight chest pain after the second EBV implantation, and HRCT revealed some pleural effusion, which was localized to the minor fissure and absorbed spontaneously.