Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Moderate cardiomegaly is stable . Widening mediastinum has improved . Bibasilar atelectasis have minimally improved . There is no evident pneumothorax . previously seen pneumoperitoneum is less conspicuous than before . Left chest tube remains in place . Sternal wires are aligned . Patient is status post CABG and AVR
    OUTPUT:
    
Mildly improved bibasilar atelectasis . Pneumoperitoneum is less conspicuous than before