Prediction of Mortality and Survival of Patients After Cardiac Surgery Using Fuzzy EuroSCORE System and Reliability Analysis

Cardiac surgery is an important medical treatment for coronary vessel patients. Different models have been introduced to determine the risk factors related to side effects of this operation. The goal of this research is to study EuroSCORE (European System for Cardiac Operative Risk Evaluation) as a useful method for predicting the risk of mortality after cardiac surgery, and to introduce a new way of inference, called Fuzzy EuroSCORE. In addition, a systems reliability analysis will be used to calculate the survival possibility of patients after a certain time period after cardiac surgery. To model and simulate the suggested system, eight important parameters of EuroSCORE table are chosen using expert's knowledge and a new method is applied based on a fuzzy inference system. To calculate the risk of mortality after cardiac surgery, the patients are categorized into 3 different groups of low risk, medium risk, and high risk. The range of the mortality risk is determined by appropriate medical data in the fuzzy EuroSCORE system. Additionally, a defect density function for the cardiovascular problem is suggested using the systems reliability analysis. Finally, the prospect of patient's survival after a certain time period after cardiac surgery is predicted.