Elevated preoperative C reactive protein level as an independent risk factor for mortality after coronary bypass graft surgery

Introduction Perioperative risk estimation score systems used in cardiac surgical daily practice contains variables about preoperative laboratory parameters. C reactive protein was studied as a potential risk factor in cardiovascular/coronary artery diseases (CAD). We aimed to identify the relationship between the preoperative C reactive protein level and surgical patients postoperative mortality. Methods Current study was performed in a cardiac surgery center at Semmelweis University, Budapest, Hungary. During a retrospective analysis patients who underwent coronary artery bypass graft surgery were examined between 2009 and 2019. Routine preoperative patient and laboratory parameters, basic surgical variables were collected. The effect of preoperative C reactive protein and overall mortality was observed as primary outcome. After descriptive statistics clustering was performed. Low CRP level was coded below 1,99, normal between 2 and 4,99, elevated between 5 and 9,99 and high above 10mg/L. Survival analysis (Kaplan-Meier method) and Cox-regression were performed using clusters. Results Totally 1010 patients were enrolled, 75.2% were male. Median age was 66 years (IQR: 61-72ys), the median follow-up time was 899 days (IQR: 482-1473 days). During follow-up 144 patients (14.26%) has died. Elective surgery was 26.34%, urgent 57.03% and acute/rescue 16.63% of the cases. According to CRP level: 43.66% was low, 29.90% normal, 13.37% elevated and 13.03% high. In the aspect of survival there was a significant difference between normal and elevated (p=0.002) and normal and high (p Discussion Even the mildly elevated preoperative C reactive protein level could be an independent risk factor in patients undergoing coronary artery bypass grafting. Consideration of the preoperative CRP level could be a useful supplement to general risk estimation score systems.