Here is a short video of Charles Lebo (VP and CISO of Kindred Healthcare) discussing the information security challenges of big data.
https://www.youtube.com/watch?v=Gje-RX-OXlA
He discusses how the enormous amounts of data generated in healthcare creates challenges of retention and protection. He also addresses ransomware and threats to the healthcare delivery system itself. It is one of many videos and articles you can find on INFORMS Editor's Cut: Healthcare in the Age of Analytics:
http://pubsonline.informs.org/editorscut/healthcareanalytics