What is the Significance of Elevated Troponin I in Children and Adolescents? A Diagnostic Approach.
Yoldaş T, Örün UA.
Pediatr Cardiol. 2019 Dec;40(8):1638-1644. doi: 10.1007/s00246-019-02198-w. Epub 2019 Sep 4.
Take Home Points:
- A single-center evaluation of children with no known prior heart disease, who presented with elevated troponin I, showed association with diverse cardiac and noncardiac pathologies.
- The most frequent cause of elevated troponin I is myopericarditis (46%). Perimyocarditis is associated with higher peak troponin I levels and takes a long time to normalize.
- Most frequent non-cardiac causes include drug intoxication, carbon-monoxide poisoning. Intensive inhalation beta-agonist use in acute asthma and lower respiratory tract infections.
- A careful history, physical examination, Electrocardiogram, and Echocardiogram to evaluate function should form the basis for differentiating cardiac and noncardiac etiologies. CT angiography and Magnetic Resonance Imaging were performed in few patients.
- Unlike adults, coronary involvement is rare and cardiac catheterization is not routinely warranted except when rare pathology is suspected.
Commentary from Dr. Venu Amula MD (Salt Lake City), section editor of Pediatric Cardiology Journal Watch: Troponin I is an important cardiac biomarker and its elevation in adult patients signifies coronary artery disease. Myocardial injury and elevated troponin, though rare in children, create considerable anxiety among pediatric providers. In the current study, Yoldas et al aim to evaluate the significance of elevated Troponin I in a retrospective cohort of children less than 18 years of age admitted to a single-center between 2007 – 2018. They excluded children with a history of congenital heart disease and those requiring or having undergone cardiac surgery within the previous year. Neonates with birth asphyxia and sepsis were also excluded. For those who met inclusion criteria demographics, clinical and other diagnostic data were abstracted from medical records and analyzed using descriptive statistics.
Troponin elevation was defined as >0.06 ng/ml per the institute’s laboratory standard. Of the patients with elevated Troponin I, ECG findings, echocardiography and degree of troponin elevation were evaluated along with the final diagnosis sorted by cardiac and non-cardiac etiologies. The peak troponin levels were also compared between those with cardiac and noncardiac etiologies.
They screened 972 patient records and found 759 subjects meeting the study criteria. Evaluation of troponin was done for the most common indication of chest pain and syncope within 2 weeks of presentation. The most common cardiac causes of raised troponin were myopericarditis (46%), perimyocarditis (18%), cardiomyopathy (15%), followed by dysrhythmias (12%). The most common indication for performing troponin I test in the non-cardiac group was to investigate cardiac involvement in drug intoxications. The other reasons were carbon monoxide Poisoning and respiratory symptoms. Patients with myopericarditis and perimyocarditis had distinct characteristics of troponin elevation. Patients with perimyocarditis had higher peak troponins and also took a long time to negative troponin, not surprising given the predominance of myocardial inflammation.
The study provides a framework for differential diagnosis of elevated troponin I testing in children with no congenital heart disease. Providers should be wary of the implications of routine testing of troponin I levels. A careful review of history, indication for testing, physical examination findings should be corroborated by ECG and echocardiogram to interpret the elevated troponin I levels. Short of this, providers may produce an undue burden of anxiety for patients and themselves.