Predictive value of high-sensitive cardiac troponin T (cTnT) for adverse cardiac events in patients undergoing primary total knee arthroplasty (TKA).

BACKGROUND

Elevated high-sensitive cardiac troponin T (cTnT) is a well-known biomarker to predict cardiac events following non-cardiac surgery. However, further information regarding high-sensitive cTnT in orthopedic surgery, especially total knee arthroplasty (TKA), is not present yet. This study aims to gain further insight into the predictive value of high-sensitive cTnT in adverse cardiac events in patients accepting TKA.

METHODS

We performed a prospective study in our hospital with the aim to enrolling 789 consecutive patients. Included patients who underwent TKA had mean ages of 65 years, and 64.9% were female. High-sensitive cTnT measurements were performed for study purposes before operation and on 1st postoperative days respectively. Postoperative cardiac events (POCE) 2 months and 2 years postoperatively were used to be evaluated for present study and defined short-term and long-term POCE respectively. The cut-off value of high-sensitive cTnT predicting patients at increased risks of POCE was evaluated by the Receiver Operating Characteristic (ROC) curve analysis.

RESULTS

Mean preoperative, postoperative cTnT and difference value between preoperative and postoperative cTnT (D-cTnT) were 20, 32, 12 ng/L respectively. 2-month and 2-year cardiac event rate following TKA were 2.3% and 3.4%. Using difference value between preoperative and postoperative cTnT (D-cTnT) to predict short-term cardiac events, the best cut-off was 23 ng litre-1, with an AUC of 0.84 (95% CI: 0.79-0.89, p < 0.001), which was better in comparison to preoperative and postoperative cTnT. In contrast, using preoperative cTnT to predict long-term cardiac events, the best cut-off was 25 ng litre-1 with an AUC of 0.78 (95% CI: 0.73-0.83, p < 0.001), which was better in comparison to postoperative and D-cTnT.

CONCLUSIONS

D-cTnT best predicted short-term POCE in comparison to preoperative and postoperative cTnT, while preoperative cTnT level best predicted long-term POCE in comparison to postoperative cTnT and D-cTnT.