Prognostic role of a preoperative troponin elevation in patients undergoing urgent or emergency noncardiac surgery: a pooled analysis

Abstract

Background 10% of the surgeries performed worldwide each year are urgent/emergency surgeries, with 3-fold higher mortality than elective procedures. Preoperative troponin elevation is a well-established risk marker in elective surgery, but prognostic value in urgent/emergency surgeries remains poorly defined. Purpose We aimed to determine the relationship between baseline preoperative troponin and composite outcome of death, MINS, heart failure, atrial fibrillation, and non-fatal cardiac arrest at 30-days. Additionally, we assessed the relationship between time from troponin measurement to surgery and composite outcome. Methods We performed a pooled individual participant data analysis of VISION-1 and POISE-3, including patients >45years-old who had urgent/emergency noncardiac surgery and at least one preoperative troponin measurement. We used multivariable Cox proportional hazards models to determine if preoperative troponin elevation predicted the primary outcome. We assessed time from troponin measurement to surgery based on troponin status in POISE-3 (physicians not always aware of preoperative troponin values in VISION-1). Mediation analysis assessed whether time from troponin measurement to surgery mediated the association of preoperative troponin with cardiovascular outcomes. Results Among 5,275 patients, 1,080 had preoperative troponin measured, of whom 242 (22.4%, 95%CI 20.1–25%) were elevated. The primary outcome occurred in 47.5% (95%CI 41.3–53.8) with preoperative troponin elevation versus 11.1% (95%CI 9.1–13.4) without. Increasing age (aHR1.03,95%CI1.02-1.05), preoperative troponin elevation (aHR3.67,95%CI 2.65–5.09), and vascular surgery (aHR1.77,95%CI1.05–2.97) predicted the primary outcome. Preoperative troponin elevation was associated with longer time to surgery (median 22 vs. 18.6 hours) in POISE-3, but mediation analysis indicated that only 3.3% of the association between preoperative troponin elevation and cardiovascular outcomes was mediated by delayed time to surgery (95%CI 2.5–12.4,P=0.277). Conclusions Preoperative troponin elevation is independently associated with an increased risk of death or cardiovascular complications after emergency/urgent surgery. Although patients with preoperative troponin elevation had delayed time to surgery, it did not mediate worse cardiovascular outcomes.