Writing Committee for the VISION Study Investigators, JAMA 2017 Apr 25; 317:1642
Most troponin elevations were not obviously symptomatic.
In a 2014 study, investigators showed that even modestly elevated non–high-sensitivity troponin T levels during the 3 days after noncardiac surgery were associated independently with excess 30-day mortality (NEJM JW Gen Med Apr 1 2014 and Anesthesiology 2014; 120:564). Now, this team has performed a similar multicenter study using a high-sensitivity troponin T (hsTnT) assay in nearly 22,000 patients (age, ≥45) undergoing inpatient noncardiac surgery with general or regional anesthesia. Patients’ hsTnT levels were measured 6 to 12 hours after surgery, and daily for 3 days; the manufacturer considers levels ≥14 ng/L as abnormal (note: units for hsTnT are ng/L; units for non–high-sensitivity TnT are usually ng/mL).
Overall, 1.2% of patients died within 30 days. Elevated hsTnT significantly and independently predicted higher 30-day mortality. For example, among about 4000 patients with peak postoperative hsTnT between 20 and 65 ng/L, 30-day mortality was 3%. Mortality increased further at higher peak hsTnT levels, and several nonfatal cardiac outcomes correlated with elevated hsTnT. An absolute change of ≥5 ng/L in hsTnT across two measurements in an individual patient also was associated with 3% mortality at 30 days. Importantly, 93% of patients with hsTnT elevations in the range predicting elevated 30-day mortality had no cardiac ischemic symptoms. Only 11% of patients with elevated hsTnT levels had a potentially nonischemic etiology of elevated hsTnT (e.g., sepsis, pulmonary embolism).
The assumption here is that relatively modest elevations in hsTnT during or just after noncardiac surgery can represent potentially clinically important ischemic myocardial injury that is often initially asymptomatic or unrecognized. The question is whether perioperative troponin levels should be measured routinely (or in selected high-risk subgroups) after noncardiac surgery. Evidence-based interventions shown to improve outcomes in such patients with asymptomatic perioperative troponin elevations are lacking, but a clinical trial examining use of dabigatran for this purpose is underway