Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is normal . Multiple sternal wires and mediastinal clips denote prior cardiac surgery . A left - sided pacemaker generator pack projects leads into the right atrium and ventricle . Since the ___ examination , there has been resolution of a left basilar opacity . No new opacity is detected . There is no pneumothorax or pleural effusion . The central pulmonary vessels are normal in caliber .
    OUTPUT:
    
No acute intrathoracic process .