High-sensitivity Cardiac Troponin I In Patients With Arrhythmia

Background/Objectives The role of high-sensitivity cardiac troponin I (hs-cTnI) as a biomarker in arrhythmia patients remains controversial. This study aimed to (1) investigate hs-cTnI concentrations in patients with arrhythmias and (2) determine the relationship between hs-cTnI levels and various clinical and subclinical factors, such as coronary artery disease (CAD) and other biomarkers. Methods A cross-sectional study was conducted, enrolling 273 patients (149 males, 124 females; aged 18–96) randomly selected from the Arrhythmia Treatment Department of Cho Ray Hospital. Plasma hs-cTnI levels were measured using a three-step immunoassay with direct luminescence detection on the ADVIA Centaur (Siemens) system. Results The median (interquartile range) hs-cTnI concentration for the entire arrhythmia patient group was 17.4 (4.77–97.7) pg/mL. Hs-cTnI levels were significantly higher in patients with ventricular arrhythmias (40.4 [14.4–790.2] pg/mL) compared to those with non-ventricular arrhythmias (14.5 [4.7–83.6] pg/mL) (p = 0.012). Similarly, hs-cTnI levels were significantly elevated in arrhythmia patients with concomitant CAD (71.9 [14.1–341.3] pg/mL) compared to those without (13.2 [4.3–65.2] pg/mL) (p < 0.001). Hs-cTnI levels showed a weak correlation with CK-MB (r = 0.150, p = 0.019) but a strong, significant correlation with NT-proBNP (r = 0.509, p = 0.003) and White Blood Cell (WBC) count (r = 0.548, p = 0.001). Conclusions This study demonstrates elevated hs-cTnI levels in arrhythmia patients, particularly in subgroups with ventricular arrhythmias and concurrent coronary artery disease. The strong correlations found between hs-TnI, NT-proBNP, and WBC suggest a potential association between subclinical myocardial injury, hemodynamic stress (heart failure), and inflammation in the pathophysiology of arrhythmias