Troponin Testing for Assessing Sepsis-Induced Myocardial Dysfunction in Patients with Septic Shock

Abstract

(1) Background: Myocardial dysfunction in patients with sepsis is not an uncommon phenomenon, yet reported results are conflicting and there is no objective definition. Measurement of troponin may reflect the state of the heart and may correlate with echocardiographically derived data. This study aimed to evaluate the role of admission and peak troponin-I testing for the identification of sepsis-induced myocardial dysfunction (SIMD) by transthoracic echocardiography (TTE). (2) Methods: This was a retrospective cohort study using a prospective registry of septic shock at an Emergency Department from January 2011 and April 2017. All 1,776 consecutive adult septic shock patients treated with protocol-driven resuscitation bundle therapy and tested troponin-I were enrolled. SIMD was defined as left ventricular (LV) systolic/diastolic dysfunction, right ventricular (RV) diastolic dysfunction, or global/regional wall motion abnormalities (WMA). (3) Results: Of 660 (38.4%) septic shock patients with an elevated hs-TnI (≥0.04 ng/mL) at admission, 397 patients underwent TTE and 258 cases (65%) showed SIMD (LV systolic dysfunction (n = 163, 63.2%), LV diastolic dysfunction (n = 104, 40.3%), RV dysfunction (n = 97, 37.6%), and WMA (n = 186, 72.1%)). In multivariate analysis, peak hs-TnI (odds ratio 1.03, 95% confidence interval 1.01⁻1.06, p = 0.008) and ST-T wave changes in the electrocardiogram (odds ratio 1.82, 95% confidence interval 1.04⁻2.39, p = 0.013) were associated with SIMD, in contrast to hs-TnI level at admission. The area under the curve of peak hs-TnI was 0.668. When the peak hs-TnI cutoff value was 0.634 ng/mL, the sensitivity and specificity for SIMD were 58.6% and 59.1%, respectively. 4) Conclusions: About two-thirds of patients with an elevated hs-TnI level have various cardiac dysfunctions in terms of TTE. Rather than the initial level, the peak hs-TnI and ST-T change may be considered as a risk factor of SIMD.

Keywords: biomarker; cardiomyopathy; septic shock; troponin.

Figure 1

Example of echocardiography. (A) left ventricle ejection fraction measurement via Teichholz method. (B) measurement of mitral valve parameters. (C) measurement of E/e’ via tissue Doppler image (lateral). (D) measurement of E/e’ via tissue Doppler image (medial) Abbreviations: IVSd = interventricular septum (diastolic); LV = left ventricle; LVIDd = left ventricular internal diameter (diastolic); LVPWd = left ventricle posterior wall (diastolic); IVSs = interventricular septum (systolic); LVIDs = left ventricular internal diameter (systolic); LVPWs = left ventricle posterior wall (systolic); EDV = end-diastolic volume; EF = ejection fraction; ESV = end-systolic volume; MV = mitral valve; E = peak early diastolic transmitral flow; vel = velocity; DT = deceleration time; A = peak late diastolic transmitral flow velocity; E’ = peak early diastolic mitral annulus velocity; A’ = peak late diastolic mitral annulus velocity.

Figure 2

Flow diagram for the inclusion of patients with troponin I and a diagnosis of sepsis-induced myocardial dysfunction based on echocardiography. Abbreviations: TTE = transthoracic echocardiography, SIMD = sepsis-induced myocardial dysfunction.

Figure 3

ROC curve of hs-TnI for diagnosis SIMD. Abbreviations: ROC = receiver operating characteristic; hs-TnI = high-sensitivity troponin-I; SIMD = sepsis-induced myocardial dysfunction.