Is Bypass Surgery Risky? Mortality Risk and Success Rates

The most honest and most appropriate question our patients ask when deciding on bypass surgery is this: “What is the risk of this operation?” In this article I will explain the real risks of bypass surgery, how we calculate that risk in advance, and the success rates we have reached in modern medicine, in a way that is both transparent and easy to understand.

Risk Factors in Bypass Surgery (Age, Diabetes, Kidneys)

Every operation carries a risk, and this risk varies greatly from patient to patient. Advanced age, diabetes, kidney failure, a previous heart attack, lung disease and a reduced pumping power of the heart (ejection fraction) are the most important factors that increase risk. The risk of operations performed under emergency conditions, for example during an ongoing heart attack, is always higher than that of planned (elective) operations.

What Is EuroSCORE? How Is Surgical Risk Calculated?

Instead of assessing these factors one by one, we use internationally accepted risk scoring systems; the most widely used is EuroSCORE II. Bringing together 18 different parameters such as the patient’s age, additional illnesses, cardiac function and the urgency of the operation, this system calculates the expected in-hospital mortality risk specific to that patient as a percentage. We always calculate this score for every patient before surgery, and we base both our own decision and the discussion we will have with the patient and family on this concrete data.

Bypass Success Rates in Modern Medicine

Thanks to advances in surgical technique, anaesthesia management and intensive care support, the in-hospital mortality risk of bypass surgery in planned, low-to-intermediate risk patients is today generally in the range of 1-2%; this rate has fallen markedly compared with the 1990s, when EuroSCORE was first developed, because both patient selection and the quality of postoperative care have improved greatly. Of course this is a general average; what really matters is the calculation of your own risk profile with the scoring system.

Frequently Asked Questions

Is the risk the same for everyone? No. The risk for a young patient with no additional illnesses undergoing a planned operation is far lower than for an elderly patient with multiple additional illnesses operated on under emergency conditions.

If my EuroSCORE is high, does that mean I cannot have surgery? It does not necessarily mean you cannot; a high score allows our team to prepare more carefully for the operation by taking additional precautions. In some very high-risk patients, alternative treatment options are also considered.

Does risk calculation change the decision to operate? Yes, in some situations; in very high-risk patients, less invasive options such as stenting may come to the fore instead of surgery.

Conclusion

Although the risk of bypass surgery is real, in modern medicine it is at a fairly low level for most patients, and this risk can be calculated concretely in advance with evidence-based systems such as EuroSCORE. Our aim is to share this risk with you transparently and to make the decision together.

If bypass surgery has been recommended to you and you would like to learn your own level of risk, you can book an appointment for a detailed evaluation.

References

1. Nashef SA, Roques F, Sharples LD, et al. EuroSCORE II. Eur J Cardiothorac Surg. 2012;41(4):734-744.
2. Chalmers J, Pullan M, Fabri B, et al. Validation of EuroSCORE II in a Modern Cohort of Patients Undergoing Cardiac Surgery. Eur J Cardiothorac Surg. 2013;43(4):688-694.