Cardiopulmonary bypass (CPB) is a technique that temporarily takes over the function of the heart and lungs during surgery, maintaining the circulation of blood and the oxygen content of the body. In a small percentage of patients this causes complications that may include a stroke. This depends to a large extent on the patient’s condition, but also on the procedure. A more complicated operation carries a slightly higher risk than a simple procedure. This is where the experience of your cardiac surgical team comes becomes very important!
In an otherwise healthy patient, the risk of stroke is probably less than one percent. As always, any procedure carries the risk of complications, some of them catastrophic. In deciding what is best, you need to weigh the risks of the operation against the benefits (which really means the risks of leaving the condition treated by other means or untreated),
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Hope this helps,