Royston Jones, 39, from Brynmawr, was jailed for 15 years for the attempted murder of his wife Claire at the intensive care unit where she worked.
Plans for security staff to be on site at the hospital were also accepted.
Aneurin Bevan University Health Board said work to implement the measures was "underway".
The investment will enable CCTV to be expanded and monitored while security doors and access points will be upgraded, a health board spokesman said.
A second phase of funding was also approved for two security staff. They will initially be on duty overnight and at weekends.
A £120,000 investment has been approved to boost security at Abergavenny's Nevill Hall Hospital after a nurse was attacked on site.