Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is a left chest wall pacemaker with the leads terminating in the right atrium and likely in the coronary sinus . Patient is status post MVR with valvular placement in the appropriate positioning . Opacity at the right base has improved . There is slight blunting of the left costophrenic angle . There is no pneumothorax . The cardiomediastinal silhouette is enlarged but unchanged in appearance . There are median sternotomy wires that are intact . Osseous structures are unremarkable .
    OUTPUT:
    
New dual - chamber dual - lead pacemaker with leads in the right atrium and coronary sinus . Improved opacity at the right base .