Prognostic effect of troponin elevation in patients undergoing carotid endarterectomy with regional anesthesia – A prospective study

BACKGROUND: Myocardial injury after noncardiac surgery (MINS) occurs in 15% of patients undergoing carotid endarterectomy (CEA) with general anesthesia. Short and long-term risk of myocardial infarction (MI) and stroke have been strongly associated with the presence of MINS, with an associated mortality rate superior to 10% in the first year. Due to the absence of studies concerning CEA with regional anesthesia (RA), the present study aimed to evaluate the incidence of MINS in patients with RA and its prognostic value on cardiovascular events or death. MATERIALS AND METHODS: From January 2009 to January 2018, 156 patients from a Portuguese tertiary care medical center who underwent CEA under RA were retrieved from a prospectively gathered database. Troponin I or high-sensitive troponin I values were systematically measured in the postoperative period and studied as a binary outcome in a logistic regression model. Survival analysis was used to study the impact of MINS in time-dependent clinical outcomes such as stroke and MI. RESULTS: The incidence of MINS after CEA was 15.3%. Multivariate analysis confirmed that chronic heart failure was strongly associated with MINS (OR: 4.458, 95% CI: 1689-11.708, P < 0.001). A previously diagnosed MINS was associated with the long-term risk of MI and major adverse cardiovascular events (MACE) with hazard ratios (HR) of 3.318 (95% CI: 0.97-13.928, Breslow: P = 0.025) and 1.955 (95% CI: 1.01-4.132, Breslow: P = 0.046), respectively. CONCLUSIONS: MINS is a long-term predictor of MI and MACE. Troponin assessment after CEA should be routinely monitored in patients with a cardiovascular risk superior to 5%. Further studies concerning prophylaxis and management of MINS should be carried on, focusing on the effect of anesthetic procedure in postoperative troponin elevation.