Cardiac Troponin Kinetics in Sepsis-Induced Myocardial Dysfunction

Background: Sepsis-induced myocardial dysfunction (SIMD) is a common yet underrecognized complication of systemic infection, associated with increased morbidity, prolonged ICU stay, and higher mortality. Cardiac troponins, particularly high-sensitivity cardiac troponin I (hs-cTnI) and T (hs-cTnT), are frequently elevated in septic patients, but their kinetics, clinical significance, and mechanistic implications remain poorly defined. Distinguishing true myocardial injury from functional or supply-demand mismatch in the context of sepsis is crucial for appropriate risk stratification and management. Methods and Results: In this prospective observational study, serial measurements of hs-cTnI and hs-cTnT were performed in 178 patients admitted to the ICU with sepsis or septic shock. Troponin kinetics were analyzed over the first 7 days, in relation to echocardiographic indices of left and right ventricular function, inflammatory biomarkers, vasopressor requirements, and 30-day outcomes. A biphasic troponin release pattern was observed in patients with echocardiographic evidence of SIMD, characterized by an early rise within 24 hours and a sustained elevation associated with reduced ejection fraction, impaired strain imaging, and increased NT-proBNP. Peak troponin levels correlated moderately with IL-6, lactate, and Sequential Organ Failure Assessment (SOFA) scores. Patients with persistently elevated troponin and confirmed SIMD had a higher incidence of renal failure, prolonged mechanical ventilation, and 30-day mortality. Multivariable analysis identified early troponin trajectory as an independent predictor of adverse outcomes, outperforming static values. Conclusion: Cardiac troponin kinetics offer valuable insight into the dynamic pathophysiology of SIMD and provide a prognostic tool for early identification of high-risk patients. Incorporating serial troponin assessment into routine sepsis care may enhance diagnostic precision, facilitate monitoring of myocardial recovery, and inform therapeutic decisions in critically ill patients.