I am 54 years old and an ex-smoker, having quit

Patient: I am 54 years old and an ex-smoker, having quit about 20 years ago. Over the past few mornings I’ve been waking up to a rattling sound when I exhale. No other symptoms except a scratchy voice during the day. The rattle goes away after a single cough. Should I be concerned? Otherwise I am in excellent health.

Symptoms: Rattling in lungs in morning

Doctor: