Performance, Data & Outcomes

In keeping with guidance from the NHS and Surgical Royal Colleges, all hospitals undertaking Cardiac Surgery are responsible for publishing unit and surgeon specific performance and outcome data. The information contained in this report of Cardiac Surgery at Spire Hospital Southampton is for the time period April 2012 to March 2015. This is in keeping with the most contemporary outcome data published for the UK by the Society for Cardiothoracic Surgery in the UK and Ireland (www.scts.org). In various graphs and charts the time periods are listed as follows for simplicity:

2012/13 - 1 April 2012 to 31 March 2013
2013/14 - 1 April 2013 to 31 March 2014
2014/15 - 1 April 2014 to 31 March 2015

The data reported is for all patients, both NHS and private, having heart surgery during this three year period.

Graph 1 – Cardiac Surgical Case Mix at Spire Southampton Hospital

This graph shows Cardiac Surgical activity performed at Spire Southampton by all cardiac surgeons during the period 1 April 2012 to 31 March 2015. The graph shows the number and percentage of each type of heart surgery done at Spire Southampton Hospital. The number of operations is shown on the line going up the left hand side. The percentage (%) underneath each coloured bar shows how much of Spire Southampton’s heart surgery is made up of each procedure type.

The key underneath the graph shows what procedure(s) each coloured bar shows. The abbreviations used are explained below:

  • Isolated: This procedure has been carried out on its own. No other procedures were done during the same operation
  • CABG: Coronary artery bypass grafting
  • AVR: Aortic valve replacement
  • MV: Mitral valve procedure (repair or replacement)
  • Other: Any procedure not in the above categories. Examples are any redo (second time) procedures, double valve procedures, major aortic surgery, cardiac tumours, pericardiectomy etc.

This is the format used on the website (www.scts.org) of the Society for Cardiothoracic Surgery in Great Britain and Ireland (SCTS). More information about these procedures can be found in the "procedures" part of this website as well as on the SCTS website "about cardiothoracic surgery" section.

The data shows that the case mix in Southampton is varied and complex and is in keeping with other advanced units in the United Kingdom. Fewer than 40% of cases are isolated CABGs and fewer than 20% are isolated AVRs. The percentage of combined AVR and CABGs as well as mitral procedures and all ‘Other’ surgery consequently represents 40% of the workload at Spire Southampton.

Graph 2 – Case Mix at Spire Southampton versus the rest of the UK

The most up-to-date Adult Cardiac Surgical data for the United Kingdom shown on the SCTS website is for the period April 2011 to March 2014 and so an absolute comparison cannot be made with the more current Spire Hospital Southampton data. This graph shows the Case Mix at Spire Southampton from April 2012 to March 2015 in comparison to the average for all the hospitals in the UK from April 2011 to March 2014. It demonstrates that Spire Southampton Hospital has a case mix that is more complex than the national average. There are fewer isolated CABG procedures and consequently a greater percentage of more complex valve and ‘Other’ procedures.

Graph 3 – Annual Performance and Case Mix: March 2012 to April 2015

This shows the number of cases and case mix for the three years in question (April 2012 to March 2015). The Graph shows consistency in the complexity of cases with a trend of increasing activity during the three years.

Graph 4 – Survival After Heart Surgery at Spire Southampton (2012 – 15)

This graph shows the survival rate for Spire Hospital Southampton as the percentage of patients who do not die before being discharged from hospital. The data on the SCTS website shows risk adjusted survival in order to allow comparisons between hospitals. Some hospitals do more complicated surgery on patients who are sicker, whilst others do fairly routine surgery. Comparisons can only be made if the mortality rate is ‘risk adjusted’ to take into account the difficulty of each operation and the ‘frailty score’ of the patients. The average risk adjusted survival for all hospitals in the United Kingdom for the period April 2012 to March 2015 is 97.5% and this is shown as a horizontal line in this graph. The actual, non-risk-adjusted, survival for the period April 2012 to March 2015 at Spire Southampton Hospital is 99.6% and is shown as a blue dot. This is well above the UK average for the same time period. A direct comparison of risk adjusted data cannot be made because the Spire data is the actual survival and not the risk adjusted survival. If the survival was ‘risk adjusted’ it could, of course, be even higher and certainly cannot be lower than 99.6%. Data from Spire Hospital Southampton has now been submitted to NICOR (National Institute for Cardiac Outcomes Research) for inclusion when data publication is updated on the SCTS website (www.scts.org) to the April 2013 to March 2016 time period. This will confirm the outstanding outcomes at Spire Southampton compared to the rest of the UK.

Graph 5 – Annual Survival: March 2011 to April 2014

Graph 5a – Mortality after All Operations Spire vs UK

The SCTS website also includes a so-called "blue book on line". This gives other information about cardiac surgical activity such as how many operations are carried out in the United Kingdom each year, the actual non risk-adjusted survival outcomes of the operations, the expected outcomes of the operations, patient and surgical risk factors that are important and long-term outcomes of surgeries.

Graph 5a shows actual in-hospital mortality at Spire Southampton Hospital after all heart operations in the three years in question and, as a comparison, actual mortality for 2010 to 2013 in the UK as a whole as published in the blue book on line. Nationally actual mortality for all cardiac surgery is close to 3%, which is significantly greater than at Spire Southampton Hospital.

Graph 5b – Mortality after Isolated CABG Spire vs UK

Graph 5c – Mortality after Isolated AVR Spire vs UK

Similar comparative data between Spire Southampton Hospital in-hospital mortality and the UK average are also shown for isolated CABG (graph 5b) and isolated first-time AVR (graph 5c), the two most common procedures. Here the UK average in-hospital mortality is between 1% and 2% while at Spire Southampton it is a lot less for both procedures.

Graph 6 - Average Patient Risk Profile at Spire Southampton 2012-2015

Some risk factors like age, gender, and other medical problems can affect the outcome of heart surgery. On the SCTS website graphs are shown to demonstrate what percentage of the hospital’s patients have each risk factor (orange bar on the left) next to the average for the whole of the UK (blue bar on the right). This can tell you whether the hospital generally operates on high risk patients, and whether they specialise in doing particular types of complicated surgery, like repeat operations. Again more information is available about risk factors in the "about cardiothoracic surgery" section of the SCTS website (www.scts.org).

This graph shows the average patient risk profile data for the period April 2012 to March 2015 for Spire Southampton Hospital. A comparison is made with the UK data for the same period. The data does demonstrate certain important features. The percentage of patients at Spire Hospital Southampton who are over the age of 75 is significantly greater than the national average (30% versus 25%). The percentage of patients who are female is comparable to the national average of (28% versus 28%). Other risk factors shown demonstrate that a significant percentage of Spire Hospital Southampton patients have other medical problems or are undergoing complex surgery. This reinforces that Spire Hospital Southampton does not only perform straightforward surgery but achieves outstanding results despite a complex case mix and comparatively high-risk patient population.

Graph 7 - Performance by VLAD plot (Spire Southampton 2012 – 2015)

EuroScore is a method of calculating predicted operative mortality for patients undergoing cardiac surgery (reference www.euroscore.org) and the EuroScore calculations of an institution can be used to assess the quality of surgery and care provided there. The EuroScore establishes the risk of a patient not surviving an operation based on both patient-specific and operation-specific factors.  For example, an older patient with co-existent lung and kidney disease has a higher risk than a younger patient whose only medical problem relates to his heart. In addition, a patient who is undergoing a complex operation such as a double valve procedure is at greater risk than a patient who is only undergoing a single procedure such as a CABG alone.

Graph 7a – VLAD for All Surgeons Currently Operating at Spire Southampton

The accompanying graph (Graph 7a) demonstrates outcome data at Spire Southampton Hospital when adjusted for the logistic EuroScore and is shown as a VLAD plot (Vertical Life Adjusted Display). These plots allow trend analysis looking at sequential operative results. For this analysis the sequential operation is plotted on the horizontal axis and the patient outcome on the vertical axis. For each occurrence of the adverse event (death in this case) the plot moves one unit lower but for a positive outcome (survival) the plot moves higher. This allows a graphic representation of outcome against time. The data is adjusted to take into account the patient’s operative risk according to the logistic EuroScore. In plotting the data a patient death is proportionally offset by the pre-operative risk and similarly a credit is earned for the survival of the patient, again with the amount being proportional to the patient risk according to 50% logistic EuroScore.

Graph 7b – VLAD for Spire Southampton 2011 – 2014 (incl. Rocket Tails)

In addition, tails of distribution, so-called ‘Rocket Tails’, are shown (Graph 7b).  For a given series of operations there may be many potential outcomes that could have occurred, each of which would give rise to different VLAD values. Given exact estimates for the probabilities of occurrence of each of these, it is feasible to colour code all these potential values for the VLAD scores according to percentile ranges. Superimposing such a display on the VLAD chart provides a useful guide for interpretation, as shown in Graph 7b. The different coloured zones shown in the graph provides a ‘temperature gradient’ against which to compare the track of a particular VLAD chart. The degree of displacement from the horizontal axis can easily be assessed in terms of how it compares with the distribution of chance outcomes. The further a VLAD plot falls below the horizontal, the more concerned one should be, particularly if it enters the more extreme zones of the ‘temperature’ gradient. This graph shows risk-adjusted survival after Cardiac Surgery at Spire Hospital Southampton from April 2012 to March 2015 steadily increasing above the expected outcomes when risk adjusted for 50% logistic EuroScore.  The trend moves above the upper 1% tail after about 300 cases to finish significantly better than could be explained by what might have occurred purely by chance.

Graph 8 – Individual Surgeon Case Mix at Spire Southampton Hospital

There are currently five surgeons who perform Cardiac Surgery at Spire Southampton Hospital. Individual data are shown for the four surgeons who have operated at Spire Southampton during the entire three year period in question, as well as for Mr Theo Velissaris who has operated at Spire Southampton since 2013.

Graph 8a shows the case mix for Mr Cliff Barlow in the same format as was used in Graph 1 for the hospital as a whole. Graph 8b shows case mix data for Mr Steve Livesey, Graph 8c for Mr Sunil Ohri, Graph 8d shows data for Mr Geoff Tsang and Graph 8e for Mr Theo Velissaris. The varying case mix demonstrated in the graphs shows the different specialist interests of the surgeons. Further information on the specialist interests of these five surgeons can be found by accessing "The Cardiac Surgeons" section of this website.

Data for Individual Surgeons are shown alphabetically.

Graph 8a - Case Mix Mr Cliff Barlow Spire Southampton 2012- 2015

Graph 8b - Case Mix Mr Steve Livesey Spire Southampton 2012- 2015

Graph 8c - Case Mix Mr Sunil Ohri Spire Southampton 2012- 2015

Graph 8d - Case Mix Mr Geoff Tsang Spire Southampton 2012- 2015

Graph 8e - Case Mix Mr Theo Velissaris Spire Southampton 2013-2015

Graph 9 – Individual Surgeon Outcomes at Spire Southampton (2012-15)

In keeping with guidance from the NHS and Surgical Royal Colleges, all hospitals undertaking Cardiac Surgery are also responsible for publishing surgeon specific outcome data. This graph shows in hospital actual mortality rates of patients undergoing heart surgery for the individual surgeons at Spire Hospital Southampton. The data shows mortality as a percentage of the number of cases performed over the three years. The green line shows the risk-adjusted national average for the period 2012 to 2015 as a comparison.

Data for individual surgeons are again shown alphabetically.

Graph 9a – Survival Data for Mr Cliff Barlow Spire Southampton 2012- 2015

Graph 9b –Survival Data for Mr Steve Livesey Spire Southampton 2012- 2015

Graph 9c – Survival Data for Mr Sunil Ohri Spire Southampton 2012- 2015

Graph 9d – Survival Data for Mr Geoff Tsang Spire Southampton 2012- 2015

Graph 9e - Survival Data for Mr Theo Velissaris Spire Southampton 2013-2015

Conclusion

These data demonstrate that the cardiac surgical case mix at Spire Southampton Hospital is more complex than that in the UK as a whole. This has been maintained over the three-year period in question and, in addition, there has been an increase in the number of operations performed. The risk profile in terms of age, gender and other medical conditions of the patients is as complex as the UK average and in some areas even more so. A full range of complex operations is performed. Finally, and very importantly, the actual mortality is significantly lower than would be expected from risk profile scoring and significantly lower than the UK national average. If mortality rates were risk adjusted and compared directly with other hospitals in the UK then clearly, if anything, performance would be better still. Finally, the individual surgeons at Spire Hospital Southampton each perform a wide range of procedures and maintain outstanding performance outcomes.

Mr Clifford W Barlow DPhil (Oxon) FRCS (C/Th)
Consultant Cardiothoracic Surgeon