Background: One of the most critical health concerns of our day is acute deterioration of chronic obstructive lung disease (COPD). Detecting concurrent heart illness in these individuals might be challenging. Objective: Aims of this study were determining the diagnostic value of B-type natriuretic peptide (BNP) levels in the identification of acute COPD exacerbations (AECOPD) that were linked with left ventricular (LV) dysfunction and pulmonary hypertension. Methods: a prospective study of 100 patients with acute COPD exacerbations was done. All research participants were subjected to history taking, clinical examination, laboratory testing, blood gas analysis, echocardiography, and NT-pro BNP plasma level estimation. Results: Receiver operating characteristic (ROC) curve for BNP as a diagnostic for LV systolic dysfunction showed that area under the curve (AUC) was 0.923 at cut off point of 72.1 ng/ml with sensitivity of 93.3% and specificity of 84.6% (P<0.001).   Conclusion: Heart failure is confirmed when the average natriuretic (NT)-BNP level in the left ventricle during AECOPD is higher than normal, which should prompt quick treatment for both conditions.