AbstractBackground: Diagnosis of cardiogenic pulmonary edemarepresent a diagnostic difficulty among patients with COPDexacerbation because at many times it could have a similarclinical presentation to other causes of acute COPD exacer-bation. Lung ultrasound is an easy and reliable bed side toolthat could be helpful for diagnosis of cardiogenic pulmonaryedema in COPD patients presented with acute respiratorydistress.Aim of Study: To determine the diagnostic value of what is called B lines which are vertical lines extend from the pleural line to the bottom of the screen in a laser like distribution detected by lung ultrasound performed by the pulmonologist in diagnosis of acute cardiogenic pulmonary edema in COPD patients presented with acute exacerbation.Patients and Methods: A prospective study including fiftytwo patients was conducted in Chest and Cardiology Depart-ments, Bab-El-Sha'aria and Al-Hussin Hospitals, Al-AzharUniversity in the period between August 2019 to March 2020.All patients are presented by COPD exacerbation that wasattributed to cardiogenic pulmonary edema, echopulmonog-raphy using abdominal probein B mode scanning the supramammary and the infrascapular areas of both lungs wasperformed for all patients while the patient in setting position.Results: Among 52 COPD patients with mean age 62.5± 4.6, including 45 (86.5%) males and 7 (13.5%) was females,according to the FEV1 they was classified as severe COPD in 25 (48.1%) andwith moderate severity in 27 (51.9%) patients, all patients are decompensated by cardiogenic pulmonary edema, BNP was abnormally elevated in all patients, CXR bilateralbat wing infiltration was present in (96%) and absent in (4%) of patients. B lines was detected in 88.5% of all patients with sensitivity of 90.2% and specificity of 100%.Conclusion: Echopulmonography performed to evaluatethe lung parenchyma for detection of B lines is a simplereadily available bedside tool that ishelpful inthe diagnosisof cardiogenic pulmonary edema in patients presented byCOPD exacerbation. It could be performed in a short timeand comfortable position for the patient who is in respiratorydistress with subsequently rapid start of the appropriatemanagement.