Welcome to the Blue Book Online

This website will tell you about cardiac surgery activity and outcomes in the UK. You can find out:

This website allows access to information that is held in the UK National Adult Cardiac Surgery Audit. When a heart operation happens in an NHS hospital (and a number of the private hospitals), data is collected about the clinical condition of the patient, the operation itself, and post-operative outcomes including mortality. We have previously published these data in a series of 'Blue Books', but now see web-based access to the most up to date data as being more useful. To this end, we have replaced the paper version with this Blue Book Online. All of the processes involved in collecting and analysing the data are compliant with patient confidentiality principles and the appropriate data protection legislation. No data that can allow a patient to be identified is included on this website.

To find out more about the information displayed on this page, please refer to the Frequently Asked Questions (FAQ). All years given represent a financial year e.g. 2011 represents 1st April 2011 – 31st March 2012.

The audit is commissioned by the Healthcare Quality Improvement Partnership and managed by the National Institute for Cardiovascular Outcomes Research (NICOR) at University College London (UCL).



How many operations are carried out each year?

The number of operations undertaken each year has changed over time, and the proportion of different types of surgery has also changed; for example a greater proportion of all cardiac surgery is now made up of valve replacements or repairs than it was 10 years ago, and the proportion that is isolated coronary artery surgery is correspondingly smaller. In this section you can select the operation type you are interested in from the drop down menu and then either select 'All Hospitals' or select the specific hospital you would like to see data for. The table and accompanying graph will then display the number of that type of procedure undertaken each year in the selected group.

Disclaimer: The number of procedures during each financial year reflects the number of operations uploaded to the central database as opposed to the number of procedures actually performed. Over the past ten years case attainment is believed to have been complete for all NHS hospitals.

YearNumber of operations


What are the actual outcomes of the operations?

Heart surgery is major surgery. There has been a lot of attention paid to the mortality rates after surgery in recent years, which has encouraged service improvements and driven the overall risk of surgery down. When we talk about 'mortality rates' in this section, we are talking about the percentage of patients who died in hospital (before they were discharged) after having a heart operation. The mortality varies for different operation groups; for example the risk of isolated first time coronary artery surgery is lower than for the more complex combined aortic valve and coronary artery surgery. The mortality rate each year is given in the following table and graph – the particular operation group can be selected from the drop-down menu.

YearMortality (%)


What are the expected outcomes of the operations?

The risk associated with cardiac surgery depends on a number of different factors including the type of surgery, the status of the heart for that particular patient and that patient's other associated illnesses. The logistic EuroSCORE is a widely used formula to predict mortality based on these risk factors. In this section we have given the average logistic EuroSCORE (the predicted mortality rate) for the various operations, which can be selected from the drop down menu. The way that predicted risk of death has changed over time can be seen in the table and chart. In general more high risk patients have been coming to cardiac surgery year on year in the UK. Despite this the overall mortality rate is decreasing, indicating better quality of care for patients.

YearPredicted mortality (%)


What risk factors are important and how often do they occur?

Risk factors such as your age, gender and type of surgery can affect the outcome of cardiac surgery.

In this section we have included the incidence of the various risk factors that are collected in the dataset. By selecting the different types of operation from the dropdown menu you can see how they have changed over time. By clicking on the Help next to each risk factor you can see a description of that risk factor, and why it is important in determining the outcomes following cardiac surgery. The full definitions of the risk factors are available at www.euroscore.org.

Year 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015
The age of the patient at the time of surgery is an important determinant of outcome following surgery.  If all other things are equal older patients are more at risk than younger ones. In general the trend over recent years has been for increasingly old patients to come to cardiac surgery. Age (years) 65.9 65.9 66.3 66.3 66.6 66.6 66.6 66.5 66.5 66.5
Women are more at risk following cardiac surgery than men for many, but not all, of the different operation types. The reasons for this are not fully understood. Female (%) 27.0 27.1 27.5 27.2 27.7 28.0 27.6 27.5 27.5 28.1
If a patient's clinical condition is so serious that they cannot wait to have their operation on an operating list on the next day during normal working hours, that is classified as an emergency procedure. Emergency operations are associated with high mortality rates. Emergency or salvage surgery (%) 3.7 3.8 3.2 3.1 3.5 3.4 3.6 3.6 3.4 3.9


What are the longer term outcomes of surgery?

All of the other survival information on this website is based on whether a patient is alive when discharged from hospital. Here we show as 'survival curves' the probability of survival after a specific number of days for different heart operations with different variables. This is based on the information we have about actual patient survival rates for procedures performed in England and Wales from April 2001.

Survival curves give the chance of survival (vertical axis) versus time in days (horizontal axis).

  • The vertical axis runs from 1 (100% chance of survival) at the top to zero (0% chance of survival) at the bottom.
  • The horizontal axis starts from 0 (day of operation) and runs up to the maximum follow-up time.
  • By using the drop down menus, you can see the survival curves with different variables such as operative urgency and the complexity of the operation. These are shown as coloured lines.

It is important to remember that the average age for having heart surgery is around 67 years and, given enough time, everyone's chance of survival drops to 0% (even if they have not had surgery).

Curves that go down steeply show that more patients die in the days after surgery than a curve that is more level. This would probably be due to an operation being complex, or patients being very unwell prior to their surgery.

All survival curves display descriptive data only. Where there are two survival curves included in a plot these are not adjusted for patient risk factors. Patient risk factors are known to differ between procedure groups and therefore these plots should not be used to directly compare outcomes between different procedure groups.