University Hospitals Birmingham NHS foundation trust is being reviewed by the Care Quality Commission because data has shown that its death rates for heart surgery are substantially outside the acceptable range.

All surgery carries risk but by comparing data from heart surgeons around the country it is possible to analyse whether the mortality rate is higher than it should be. Here the unexpected figures have led to an investigation into what may be the cause.

The report is awaited, but the chief inspector of hospitals at the CQC has said that inspectors have found concerns with the "safety, effectiveness and responsiveness of the service."

At present no individual cases have been reported where failings at the Trust have caused deaths which could otherwise have been avoided.