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Updated: May 19, 2026
Digital PCR for Quantifying Circulating MicroRNAs in Acute Myocardial Infarction and Cardiovascular Disease
Published on: July 3, 2018
Circulating microRNAs after cardiac arrest
Pascal Stammet1, Emeline Goretti, Mélanie Vausort
1Department of Anaesthesia and Intensive Care, Centre Hospitalier, Luxembourg, Luxembourg.
Objective:
Prediction of clinical outcome after cardiac arrest is clinically important. While the potential of circulating microRNAs as biomarkers of acute coronary syndromes is an active field of investigation, it is unknown whether microRNAs are associated with outcome in cardiac arrest patients.
Design:
Prospective, single-center proof-of-concept study.
Setting:
Eighteen-bed adult general intensive care unit of an academic tertiary care hospital in Luxembourg.
Patients:
Twenty-eight patients with cardiac arrest treated by therapeutic hypothermia after cardiac resuscitation were enrolled.
Measurements And Main Results:
Blood samples were obtained at 48 hrs after cardiac arrest for the determination of microRNA levels and neuron-specific enolase. Neurological outcome was determined by the cerebral performance category at discharge from the intensive care unit and at 6-month follow-up. Analysis of microRNA arrays and quantitative assessment by polymerase chain reaction identified two microRNAs, miR-122 and miR-21, overexpressed in patients with poor neurological outcome (cerebral performance category 3-5, n = 14) compared to patients with favorable neurological outcome (cerebral performance category 1-2, n = 14) (48-fold and three-fold, respectively). In vitro experiments showed that both miR-122 and miR-21 are produced by neuronal cells, indicating that the elevation of circulating levels of these microRNAs after cardiac arrest may reflect brain damage. miR-122 and miR-21 predicted neurological outcome with areas under the receiver operating characteristic curve of 0.73 and 0.77, respectively. Patients within the highest third of miR-122 or miR-21 values had elevated mortality rate (p = .02). Neuron-specific enolase was an accurate predictor of neurological outcome (areas under the receiver operating characteristic curve = 0.98) and mortality (p < .001). MicroRNA levels were not associated with myocardial damage or activation of inflammation.
Conclusions:
As compared to neuron-specific enolase, circulating microRNAs are modest but significant predictors of neurological outcome and mortality in this small group of patients with cardiac arrest. This motivates assessing the prognostic value of microRNAs in larger cohorts of cardiac arrest patients.
Insights
Circulating microRNAs, such as miR-122 and miR-21, show potential as biomarkers for predicting neurological outcome and mortality in cardiac arrest survivors. While modest predictors compared to neuron-specific enolase, their prognostic value warrants further investigation in larger patient cohorts.
Area of Science:
- Biomarkers
- Neuroscience
- Intensive Care Medicine
Background:
- Predicting clinical outcomes after cardiac arrest is crucial for patient management.
- Circulating microRNAs are being investigated as biomarkers for acute coronary syndromes.
- The prognostic role of microRNAs in cardiac arrest patients remains largely unknown.
Purpose of the Study:
- To investigate the association between circulating microRNA levels and clinical outcomes in cardiac arrest patients.
- To determine if specific microRNAs can predict neurological outcome and mortality post-cardiac arrest.
- To compare the predictive value of microRNAs with established biomarkers like neuron-specific enolase.
Main Methods:
- Prospective, single-center proof-of-concept study involving 28 cardiac arrest patients treated with therapeutic hypothermia.
- Blood samples collected 48 hours post-cardiac arrest for microRNA and neuron-specific enolase level determination.
- Neurological outcome assessed using the cerebral performance category at ICU discharge and 6-month follow-up.
Main Results:
- Two microRNAs, miR-122 and miR-21, were significantly overexpressed in patients with poor neurological outcome.
- In vitro studies indicated that miR-122 and miR-21 are produced by neuronal cells, suggesting they may reflect brain damage.
- miR-122 and miR-21 demonstrated moderate predictive accuracy for neurological outcome (AUC 0.73-0.77) and were associated with increased mortality.
- Neuron-specific enolase showed higher accuracy in predicting outcome (AUC 0.98) and mortality.
Conclusions:
- Circulating microRNAs (miR-122, miR-21) are modest but significant predictors of neurological outcome and mortality in cardiac arrest patients.
- Neuron-specific enolase remains a more accurate predictor of outcome and mortality in this cohort.
- Further validation in larger cohorts is recommended to assess the prognostic value of microRNAs in cardiac arrest.
