Increases in serum concentrations of cardiac proteins and the prediction of early postoperative cardiovascular complications in noncardiac surgery patients

We investigated the use of measurements of serum concentrations of the card iac proteins troponins I and T as biochemical markers of myocardial cell da mage in 80 patients undergoing vascular or major orthopaedic surgery. Holte r electrocardiographic monitoring was carried out before surgery and for 3 days after surgery. Blood samples for troponins I and T and creatine kinase -MB isoenzyme were taken on each of these 4 days. Outcome was assessed at 3 months using a patient questionnaire, general practitioner follow-up and c ase notes review. Silent postoperative myocardial ischaemia was detected in 21 patients; increases in troponins I and T and creatine kinase-MB occurre d in four, six and 17 of these patients, respectively. Eight patients suffe red major postoperative complications (cardiac death, myocardial ischaemia, congestive cardiac failure, unstable angina and cerebrovascular accident) and 21 minor complications (poorly controlled hypertension needing increase d or new additional treatment, palpitations, increased tiredness or shortne ss of breath in the absence of known respiratory disease). There were no as sociations between postoperative ischaemia and cardiac protein concentratio ns. The relative odds for the associations of major adverse outcome at 3 mo nths after surgery and postoperative ischaemia or increased serum concentra tions of the three proteins were 5.39 [95% confidence intervals 1.16-27.67] for postoperative ischaemia; 5.64 [1.07-31.00] for creatine kinase-MB isoe nzyme; 17.00 [2.20-116.54] for troponin T and 13.20 [1.12-135.00] for tropo nin I. We found troponin T to be the only prospective marker for both major and minor cardiovascular complications (relative odds 10.65 [1.26-252.88]) .