Acute Heart failure (AHF) is a common cause of acute exacerbation of chronic obstructive pulmonary disease (AECOPD). This association is frequently underestimated with regard to the difficulty of clinical diagnosis. The investigators expect that the application of the lung ultrasound could be useful in this issue.

Chronic obstructive pulmonary disease (COPD) is a frequent disease in our population affecting mainly the elderly and males. Dyspnea is the most common reason for consultation for patients with COPD in ED. Distinguishing between pulmonary and/or cardiac origin can be challenging.Physical examination, laboratory findings and radiography are imperfect. Lung ultrasound sonography (LUS) has recently gained a large place in the diagnosis of heart failure (HF), but its contribution to the diagnosis of HF in COPD remains poorly studied.

Purpose: The purpose of this study is to assess the contribution of LUS in the diagnosis of HF in COPD patients with acute dyspnea

. Physical examination, laboratory findings and radiography are imperfect, resulting in a need for sophisticated test results that delay management. Lung ultrasonography is becoming a standard tool in critical cases in the ED. the investigators aim to perform ultrasonography on COPD patients admitted to the ICU with dyspnea, comparing lung ultrasonography results on initial presentation with the final diagnosis by the ICU team. Three items were assessed: artifacts (horizontal A lines or vertical B lines indicating interstitial syndrome), lung sliding, and alveolar consolidation and/or pleural effusion, these items were grouped to assess ultrasound profiles. This study assesses the potential of lung ultrasonography to diagnose heart failure.The second aim of this study was to evaluate the inter-observer reproducibility of LUS performed by ED residents in the evaluation of cardiac causes of acute dyspnea.This study includes patients with COPD consulting for acute dyspnea. We performed a lung ultrasound on all patients included. The diagnosis of heart failure (HF) was based on clinical, radiological, cardiac-ultrasound and expert data. The LUS diagnostic performance indicators were calculated using the different cut-off proposed by the LUS score.Then the probability of AHF was defined as : low probability (LUS<15) intermediate probability (15≤ LUS<30), and high probability (LUS≥30 ).

Inclusion Criteria:

• patients with history of COPD admitted to the emergency department for dyspnea non traumatic dyspnea

Exclusion Criteria:

• instable hemodynamic or neurological status non consent to participate in the study

patients with history of COPD admitted to the emergency departmet for dyspnea