Hawkins et al.’s systemic review showed that natriuretic peptide levelsare always significantly elevated in patients with COPD and concomitant HF or leftventricle systolic dysfunction compared to those without.30 In our cohort, airflow obstruction was not associated with BNP level orcomplexity of CHD, but half of the patients in the obstruction group died duringfollow-up. Here, NPPB is linked to chronic obstructive pulmonary disease.