Pre-operative platelet-bound CD40 ligand is probably associated with peri-operative cardiac events in hip and knee arthroplasty.

BACKGROUND

Peri-operative cardiac events are common and associated with significant morbidity. A predictive biomarker would assist in pre-operative risk stratification of surgical patients. This study explored the utility of pre-operative measurements of platelet-bound CD40 ligand and other biomarkers for predicting peri-operative cardiac events in total hip or knee arthroplasty.

METHODS

Blood samples were collected from 62 patients prior to surgery and tested for the biomarkers platelet CD40 ligand, platelet factor V/Va, platelet P-selectin, high-sensitivity C-reactive protein, B-type natriuretic peptide and soluble CD40 ligand. The Revised Cardiac Risk Index was also calculated. Patients were then followed up prospectively and screened for peri-operative cardiac events by means of ECG, serial troponin I, a cardiologist's review and an interview at 6 weeks post operation.

RESULTS

Six of 62 (9.7%) patients had a cardiac event. Patients who experienced a cardiac event had higher pre-operative platelet CD40 ligand levels as measured by flow cytometry [median 0.55% vs. 0.29% (P = 0.02)]. In this sized sample, platelet CD40L was the only biomarker independently associated with cardiac events (P = 0.02), the area under the receiver-operator characteristic curve being 0.79.

CONCLUSION

In a study of this number of patients, of the six biomarkers tested, only platelet CD40 ligand was found to have a probable association with peri-operative cardiac events in hip and knee arthroplasty.