A 65-year-old man with a 40-year history of tobacco use and a chronic productive cough for several years develops more severe dyspnea and fever. He has an enlarged chest diameter and some mild...

A 65-year-old man with a 40-year history of tobacco use and a chronic productive cough for several years develops more severe dyspnea and fever. He has an enlarged chest diameter and some mild blueness to the lips. A chest radiograph shows an enlarged heart and hyperlucent lung fields but no evidence of a pulmonary infiltrate.

1. What is the most likely diagnosis?

2. What is the most likely underlying mechanism associated with this disorder?