Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Patient is status post median sternotomy and CABG . A shin is seen . There is no pneumothorax or pleural effusion . The cardiac silhouette remains mildly enlarged . Mediastinal contours are stable . No displaced rib fracture is seen , however , these radiographs has low sensitivity for the detection of such .
    OUTPUT:
    
No definite acute cardiopulmonary process .