title: Pre-operative platelet-bound CD40 ligand is probably associated with peri-operative cardiac events in hip and knee arthroplasty.
abstract: 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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: The Prince Charles Hospital, Brisbane, Qld, Australia.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Ray
authors.forename: Lorenzo J
authors.initials: LJ
authors.lastname: Calabro
authors.forename: Tilak
authors.initials: T
authors.lastname: Sirisena
authors.forename: Scott A
authors.initials: SA
authors.lastname: Crawford
authors.forename: Ross W
authors.initials: RW
authors.lastname: Crawford
authors.forename: Darren L
authors.initials: DL
authors.lastname: Walters
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019540:Area Under Curve; D001145:Arrhythmias, Cardiac / Q000453:epidemiology; D019644:Arthroplasty, Replacement, Hip; D019645:Arthroplasty, Replacement, Knee; D015415:Biomarkers / Q000097:blood; D001779:Blood Coagulation Factors / Q000032:analysis; D001792:Blood Platelets / Q000378:metabolism*; D002097:C-Reactive Protein / Q000032:analysis; D023201:CD40 Ligand / Q000097:blood*; D005260:Female; D005434:Flow Cytometry; D005500:Follow-Up Studies; D006331:Heart Diseases / Q000097:blood* / Q000453:epidemiology; D006333:Heart Failure / Q000097:blood / Q000453:epidemiology; D006801:Humans; D008297:Male; D009203:Myocardial Infarction / Q000097:blood / Q000453:epidemiology; D020097:Natriuretic Peptide, Brain / Q000097:blood; D019007:P-Selectin / Q000097:blood; D011237:Predictive Value of Tests; D011300:Preoperative Care; D019210:Troponin I / Q000097:blood
chemical_list: D015415:Biomarkers; D001779:Blood Coagulation Factors; D019007:P-Selectin; D019210:Troponin I; C037685:platelet factor V; D020097:Natriuretic Peptide, Brain; D023201:CD40 Ligand; D002097:C-Reactive Protein