The Impact of Cardiology Consultation on Medical Intensive Care Unit Patients with Elevated Troponin Levels

Background: Cardiac troponin (cTn) is mainly used to diagnose acute coronary syndrome (ACS). However, cTn can also be elevated in critically ill patients secondary to demand ischemia or myocardial injury. The impact of cardiology consultation on the clinical outcomes of patients admitted to medical intensive care unit (ICU) with elevated cTn is unclear. Methods: A retrospective analysis of medical ICU patients with elevated cTn without evidence of ACS between January 2013 through December 2018. Patients were stratified based on documentation of cardiology consultation. The primary outcome was 1-year mortality. Secondary outcomes were in-hospital and 30-day mortality, the length of stay (LOS), further cardiac testing, 30-day readmission rate, new prescription of cardiac medications, and the predictors of a cardiology consultation. Results: Of 846 patients screened, 766 patients were included, of whom 63.2% had cardiology consultation. Cardiology consultation group had longer median LOS (7 vs. 5 days, P = 0.007), additional cardiac testing (90.3% vs. 67.7%, P < 0.001), and more new cardiac medications (52.1% vs. 16.3%, P < 0.001). No difference was noted in-hospital mortality (adjusted odds ratio [aOR], 0.6, 95% CI, 0.4–1.1, P =.117), 30-day mortality (aOR = 0.8, 95% CI, 0.5–1.4, P =.425), 1- year mortality (aOR, 1.4, 95% CI, 0.9–2.2, P =.193), or cardiac-specific 30-day readmission rate (aOR, 7.0, 95% CI, 0.7–14.9, P =.137). History of coronary artery disease (CAD) was the most independent predictor for a cardiology consult (aOR, 2.2, 95% CI, 1.3–3.8, P <.001). Conclusion: Cardiology consultation for elevated cTn in medical ICU patients was associated with increased cardiac testing and LOS, without significant impact on mortality.