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 inferior vena cava collapsibility index (ΔIVC)could be useful in this issue.

Acute heart failure (AHF) is a common cause of COPD exacerbation however its role is very often underestimated. Until now, the use of echocardiography and some invasive hemodynamic exploration techniques such as the Swanganz catheter has been stated as reference. Other noninvasive diagnostic methods have been studied, such as systolic time intervals and Valsalva maneuver, but their application still difficult in patients with COPD exacerbation, especially in emergency department (ED) settings. the study aimed to evaluate the performance of a new diagnostic technique based on the measurement of the ΔIVC for the early identification of AHF in patients presenting to the ED with acute COPD exacerbation.

Inclusion Criteria:

• patient with history of COPD and admitted to the emergency departement for AECOPD

Exclusion Criteria:

• impossibility to give consent to participate in the study, non consent patients
• post traumatic dyspnea
• instable hemodynamic or neurological status

patients with history of COPD admitted to the emergency departmet for AECOPD and stable hemodynamic status