Leandro Gazziero Rech

Clinical use of ultrasensitive cardiac troponin I assay in intermediate- and high-risk surgery patients

Background. Cardiac troponin levels have been reported to add value in the detection of cardiovascular complications in noncardiac surgery. A sensitive cardiac troponin I (cTnI) assay could provide more accurate prognostic information. Methods. This study prospectively enrolled 142 patients with at least one Revised Cardiac Risk Index risk factor who underwent noncardiac surgery. cTnI levels were measured postoperatively. Short-term cardiac outcome predictors were evaluated. Results. cTnI elevation was observed in 47 patients, among whom 14 were diagnosed as having myocardial infarction (MI). After 30 days, 16 patients had major adverse cardiac events (MACE). Excluding patients with a final diagnosis of MI, predictors of cTnI elevation included dialysis, history of heart failure, transoperative major bleeding, and elevated levels of pre- and postoperative N-terminal pro-B-type natriuretic peptide (NT-proBNP). Maximal cTnI values showed the highest sensitivity (94%), specificity (75%), and overall accuracy (AUC 0.89; 95% CI 0.80–0.98) for postoperative MACE. Postoperative cTnI peak level (OR 9.4; 95% CI 2.3–39.2) and a preoperative NT-proBNP level ≥917 pg/mL (OR 3.47; 95% CI 1.05–11.6) were independent risk factors for MACE. Conclusions. cTnI was shown to be an independent prognostic factor for cardiac outcomes and should be considered as a component of perioperative risk assessment.

Valor prognóstico do fragmento N-terminal do peptídeo natriurético tipo B em cirurgia não-cardíaca

BACKGROUND Preoperative NT-proBNP has been shown to predict adverse cardiac outcomes, although recent studies suggested that postoperative NT-proBNP determination could provide additional information in patients submitted to noncardiac surgery. OBJECTIVE To evaluate the prognostic value of perioperative NT-proBNP in intermediate and high risk cardiovascular patients undergoing noncardiac surgery. METHODS This study prospectively enrolled 145 patients aged ≥ 45 years, with at least one Revised Cardiac Risk Index risk factor and submitted to intermediate or high risk noncardiac surgery. NT-proBNP levels were measured pre- and postoperatively. Short-term cardiac outcome predictors were evaluated by logistic regression models. RESULTS During a median follow-up of 29 days, 17 patients (11.7%) experienced major adverse cardiac events (MACE- 14 nonfatal myocardial infarctions, 2 nonfatal cardiac arrests and 3 cardiac deaths). The optimum discriminatory threshold levels for pre- and postoperative NT-proBNP were 917 and 2962 pg/mL, respectively. Pre- and postoperative NT-proBNP (OR 4.7; 95% CI 1.62-13.73; p=0.005 and OR 4.5; 95% CI 1.53-13.16; p=0.006) were significantly associated with MACE. Preoperative NT-proBNP was significantly and independently associated with adverse cardiac events in multivariate regression analysis (adjusted OR 4.2; 95% CI 1.38-12.62; p=0.011). CONCLUSION NT-proBNP is a powerful short-term marker of perioperative cardiovascular events in high risk patients. Postoperative levels were less informative than preoperative levels. A single preoperative NT-proBNP measurement should be considered in the preoperative risk assessment.