Hi there - janey and northern are absolutely correct, a narrative verdict is one when a death is not simply explained, and the coroner wishes to provide more details. If the coroner feels that there is 'causative effect', in that actions or omissions directly contributed to a death, it may include words such as failure / neglect / incompetence or even negligence.
As in the case for my daughter, the coroner can stipulate a Rule 43 report on the trust to force them to review aspects of their care, especially if it is thought this can prevent future deaths. Did this happen? If not done at the time, it is possible for this to be stipulated later on if another similar situation arises.
Unfortunately, there is no standard timeframe for inquests to take place, which seems a little crazy to me, as time inevitably fades memory.
You can certainly place a complaint against the hospital about their care, and they are obliged to respond to you. The hospital should have done a Root Cause Investigation Report, and you can ask to see this, and write to the chief executive if you are not satisfied with the report or its recommendations. You might also have grounds for a compensation case too, if you wished to do this, but I am not a lawyer at all, so seek legal advice on this front.
In the end, none of it changes the fact that you have lost your lovely mum though, and you might want simply to leave things as they are.