Prognostic Value of Cardiac Troponin I for In-hospital Recovery in Patients with ST-Elevation Myocardial Infarction

Introduction:
ST-elevation myocardial infarction (STEMI) remains a common cause of
cardiovascular mortality, with accurate risk stratification for the appropriate
management of the patient. Cardiac troponin I (cTnI) has been identified as
a potential prognostic biomarker, as well as in its diagnostic role.
Objective:
This study aimed to evaluate the prognostic significance of cardiac
troponin I level for in-hospital recovery and complications in patients
with STEMI.
Methods:
A cross-sectional study was conducted on 100 STEMI patients aged
30-70 years. The patients were categorized into three groups based on
serum troponin I concentration: <0.034 ng/mL (low risk), 0.034-0.12
ng/mL (intermediate risk), and ≥0.12 ng/mL (high risk). In-hospital
mortality, complications (arrhythmia, heart failure, cardiogenic shock),
and length of stay in the hospital were the primary outcomes of interest.
Statistical analysis was performed on SPSS version 26 using chi-square
tests and binary logistic regression.
Results:
The study population had a mean age of 52.5±13.1 years with 59% male
preponderance. There was a clear-cut dose-response relation observed
between troponin levels and adverse outcomes. In-hospital mortality
increased step-wise in low, intermediate, and high-risk troponin groups
(0%, 3.4%, 38.5% respectively; p<0.001). Cumulative complication
rates also followed a similar pattern (3.7%, 68.4%, 100% respectively;
p<0.001), with specific complications like arrhythmias (0%, 33.3%, 46.1%), heart failure (0%, 23.3%, 30.7%), and cardiogenic shock (1.3%, 11.6%, 23.0%). Hospital stay was also significantly related to the troponin levels, with prolonged hospitalization (>7 days) in 0%, 6.7%,
and 76.9% in respective groups (p<0.001). Multivariate analysis also
endorsed troponin ≥0.12 ng/mL as an independent predictor of mortality
with a 49-fold increased risk (OR=49.8, 95% CI: 5.3-463.2, p<0.001).
Conclusion:
The study highlights the optimal prognostic value of cardiac troponin I
levels in the prediction of in-hospital outcomes among STEMI patients.
The proposed risk stratification system can be applied to inform
decisions for clinical management, deployment of resources, and
patient care approach in acute cardiac care units.