Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Patient is status post median sternotomy , CABG , and mitral valve repair . A left - sided AICD device is noted with leads terminate in the right atrium , right ventricle , and coronary sinus , unchanged . Mild cardiomegaly is similar . The mediastinal and hilar contours are unremarkable . Pulmonary vasculature is not engorged . There is a small left pleural effusion , not substantially changed from the previous study with associated left basilar opacity likely reflective of compressive atelectasis . Right lung is clear . No pneumothorax is present . No acute osseous abnormalities demonstrated .
    OUTPUT:
    
Persistent small left pleural effusion with left basilar opacity likely reflective of compressive atelectasis . No pulmonary edema .