COPD is a heterogeneous lung condition characterized by chronic respiratory symptoms (dyspnea, cough, expectoration and/or exacerbations) due to abnormalities of the airways (bronchitis, bronchiolitis) and/or alveoli (emphysema) that cause persistent, often progressive, airflow obstruction.It is also the most common cause of deaths in patients with chronic respiratory disease, the fatality rate in USA is 0.41%.Pulmonary Hypertension is the most common serious complication in COPD patients ; which occurs in up to 30% of patients and increases the mortality rate.Smoking is the leading cause of chronic obstructive pulmonary disease (COPD) Smoking is also a trigger for COPD flare-ups.Smoking damages the air sacs, airways, and the lining of your lungs. Injured lungs have trouble moving enough air in and out, so it's hard to breathe
