Cardiff and Vale University Health Board says it has developed "a detailed action plan to make sure that we are addressing all areas" of concern, and the Royal College of Surgeons will visit again in September to see if there has been improvement.
The health board is looking at all options to increase cardiac surgery capacity, and looking at proposals to get patients treated more quickly.
Chief Executive Alun Cairns said the health board is working with surgeons "on a range of actions", and looking at what extra capacity could be provided, and improving how it manages emergency, care.
– Adam Cairns, Chief Executive of Cardiff and Vale University Health Board
We know that we can do better and we have given priority to the issues raised in the RCS report.One of the main areas of concern has been the pressure on unscheduled care, seen here in Cardiff and the Vale, Wales and across the UK, and the impact that has on other services.
A great deal of engaging with clinical teams and partners such as the third sector and Local Authorities has been done over these issues and a number of pieces of work, directed and driven by clinical staff, are now starting to take effect.