Elevated troponin level as a predictor of inpatient mortality in patients with infective endocarditis in the Southeast United States

Abstract

Background: Despite recent improvement in management, infective endocarditis (IE) continues to be associated with considerable risk of morbidity and mortality. Early identification of predictors of inpatient mortality is key in improving patient outcomes in IE. The aim of our study was to evaluate the role of serum troponin levels measurements as a marker of increased mortality. Methods: A case-control study included adult patients with IE admitted to a tertiary care hospital in east Tennessee between December 2012 and July 2017. Cases were defined as patients with definitive IE who died in-hospital; controls were patients who did not die in hospital. First patient admission was included only. Data collected included the patients' demographic and baseline clinical information, microbiological data, injection drug use status, elevated serum troponins levels. Results: Two hundred eighty three patients with definitive IE were included; median (IQR) age was 41 (30-57) years, and 153 (54%) patients were men. One-hundred sixty-four (58%) were injection drug users. The most frequent IE type was: 167 (59%) right-sided, 86 (30%) left-sided, 24 (9%) both left and right-sided, and 10 (4%) device related. The most commonly isolated organism was Staphylococcus aureus (n = 141), and 64% were methicillin-resistant. Two-hundred twelve (75%) patients had a troponin level obtained, and 57 (27%) had an elevated troponin value. Thirty-six (13%) patients died in-hospital; in-hospital mortality was associated elevated troponin values (adjusted odds ratio [adjOR], 7.3; 95%CI, 3.3-15.9), and methicillin-resistant S. aureus IE (adjOR 2.6; 95%CI, 1.2-5.8). Forty-four (16%) patients received IE valve surgery, and none of these patients died in the hospital. Conclusion: Inpatient mortality was higher in patients with IE and elevated cardiac troponin levels compared to patients with normal levels.

Association Between Elevated Cardiac Troponin Level and Clinical Outcomes in Patients with Infective Endocarditis: A Meta-Analysis

“…For patients with IE, the risk of in-hospital mortality represents the most important and commonly reported outcome [39], with all 5 studies [30][31][32][33][34] suggested the need to pay more attention in the management of IE patients with elevated cardiac troponin, given that these patients may have a poorer survival prognosis or higher risk of other complications than those with normal cardiac troponin. The review article by Burton et al [40] in 2013 included 5 studies, which explored the prognostic value of cardiac troponin levels in patients with IE.…”

“…A total of 13 studies were selected for full-text screening, following which 4 [15,[25][26][27] were excluded because of discrepancy in cardiac markers being used (not cardiac troponin) or target population being examined were of other cardiac diseases, 2 [28,29] were eliminated because the original data were not accessible. Ultimately, a total of 7 [30][31][32][33][34][35][36] studies were included for our meta-analysis (the PRISMA ow diagram was shown in Figure S1(Supplementary le 1)…”

“…Among the studies, Ipek et al [36] and Postigo et al [33] used cardiac troponin T with cut-off levels of 0.05ng/ml and 0.04ng/ml respectively as elevated cardiac biomarkers. On the other hand, studies by Tsenovoy et al [30], Lorson et al [34], and Thoker et al [31] used cardiac troponin I as biomarkers with varying cut-off values. Cardiac troponin subtype was however not speci ed in the studies by Kahveci et al [35] and Purcell et al [32] Of 687 patients with IE, most infective lesions were located in the left heart than the right heart with a person-time of 505 versus 213, multiple infections were included in both cohort.…”

“…In-hospital mortality was reported in 5 [30][31][32][33][34] studies with no obvious heterogeneity detected (Chi² = 2.65, P = 0.62; I² = 0%) and thus, xed-effects model was used. Patients with elevated cardiac troponin had a signi cantly higher in-hospital mortality than those with a normal level [OR = 5.87, 95% CI (3.37,10.21)].…”

“…Incidence of surgery (valve replacement) was assessed by 3 [33,34,36] Besides, cardiac abscesses were examined as an outcome in 3 [32,33,36] studies, comprised of a total of 262 patients with an elevated cardiac troponin level and 86 with a normal level. The incidence of cardiac abscesses of the two groups was 27.10% (71/262) and 5.81% (5/86) respectively, demonstrating a markedly increase in risk among those with a higher cardiac troponin level [OR = 3.28, 95% CI (1.01,10.62)].…”