Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Again seen are median sternotomy wires with mitral valve replacement in place . Heart size is top normal . Cardiomediastinal silhouette and hilar contours are stable with tortuosity of the thoracic aorta noted . There has been interval resolution of the right - sided pleural effusion and improvement in the small left pleural effusion . Patchy atelectasis in the left lung base persists . There is no pneumothorax . Previously seen retrosternal lucency has resolved and was likely post-operative gas .
    OUTPUT:
    
Resolution of previously noted right pleural effusion , and decreased size of trace left pleural effusion . Mild left basilar atelectasis .