Abstract 14870: Clinical Significance of Troponin Elevation in a Contemporary Hospitalized Population: Endotypes, Morbidity and In-hospital Mortality

Abstract

Introduction: Unplanned hospitalizations are commonly associated with a circulating troponin concentration >99 th percentile upper reference limit (URL). In order to better understand the clinical significance of troponin elevation, we evaluated outcomes in hospitalized patients according to cardiac endotype. Methods: We prospectively screened consecutive hospitalized patients with elevated high-sensitivity troponin-I (hs-TnI) concentrations (Abbott ARCHITECT troponin-I assay; sex-specific URL, 99 th centile: male: >34ng/L; female: >16ng/L) within a regional cardiac care network (population 650,000). A cardiology clinical team adjudicated individual patient records and assigned endotypes by consensus agreement according to the Fourth Universal Definition of Myocardial Infarction (MI). Endotypes were sub-classified into etiological category by inciting event(s). Characteristics and comorbidity were compared and outcomes recorded on virtual follow-up until June 2 nd 2020. Results: A total of 390 consecutive patients with ≥1 hs-TnI value >URL between March 1-April 15, 2020, were evaluated; 44 patients were excluded ( Duplicates: 2; Missing data: 41; Research patient: 1 ). Of 346 who qualified for inclusion, an index diagnosis of Type 1 MI (T1MI), T2MI and myocardial injury were assigned in 115 (33.2%), 79 (22.8%) and 152 (43.9%) patients, respectively. Compared with T1MI, patients with T2MI and myocardial injury had lower peak hs-TnI values (median [IQR]: 86 [250-697] vs 5020 [853-7774]ng/L; p< 0.01), lower estimated 10-year survival (40.2% vs 53.4%; p=0.002), less frequently underwent coronary revascularization (1.4% vs 45.2%; p<0.0005) and had longer inpatient stay (13.0 vs 6.1 days). Inpatient and overall mortality rates from admission to follow-up (median [range]: 71 [0-151] days) were higher among patients with T2MI and myocardial injury (19.9% vs 7.8%; p=0.004; and 26.0% vs 11.3%; Log rank (Mantel-Cox) X 2 = 1.927; p=0.003) independent of similar cardiovascular risk profiles. Conclusions: Despite lower peak circulating troponin concentrations, patients with T2MI and myocardial injury had higher inpatient mortality, lower estimated 10-year survival and longer in-hospital stay compared to those with T1MI.