Acute Carbon Monoxide Poisoning and Cardiac Magnetic Resonance: The Future Is Now

Integration of Methylation and Gene Expression Deciphered Candidate Biomarkers DAB2IP and SMYD3 in Delayed Encephalopathy After Carbon Monoxide Poisoning

AIMS

The objective of this study is to explore the regulatory role of DNA methylation in delayed encephalopathy after carbon monoxide poisoning (DEACMP) and to identify candidate epigenetic biomarkers.

METHODS

In this study, multi-omics analyses such as methylomics, transcriptomics, pyrophosphate sequencing, qRT-PCR, immunohistochemistry, and western blotting were utilized to investigate the role of epigenetic regulation and altered gene expression in the pathogenesis of DEACMP.

RESULTS

Using integrated analysis, we identified 168 differentially methylated CpGs sites, 334 differentially expressed genes, and two differentially methylated and differentially expressed genes (DAB2IP and SMYD3) in the DEACMP group. The pyrosequencing results further revealed hypomethylation of DAB2IP and hypermethylation of SMYD3. Moreover, we verified the upregulation of DAB2IP expression accompanied by the downregulation of SMYD3 expression in the DEACMP rats model.

CONCLUSION

This study, based on dysregulated DNA methylation and gene expression profiles, identified and validated two DEACMP-related genes (DAB2IP and SMYD3) that could serve as epigenetic biomarkers and potential therapeutic targets for DEACMP.

Practical Recommendations for the Evaluation and Management of Cardiac Injury Due to Carbon Monoxide Poisoning

Carbon monoxide (CO) is a relatively frequent cause of poisoning evaluated in emergency departments. The risk of neurologic injuries, such as cognitive, psychological, vestibular, and motor deficits, is 25% to 50%. However, the risk of cardiac injuries should also be considered. Among patients with CO poisoning, the mortality in patients with myocardial injury is approximately 3 times greater than that in patients without myocardial injury. In large-scale studies, up to 69.2% of patients with acute CO poisoning exhibiting elevated troponin I levels and no underlying cardiovascular illnesses had late gadolinium enhancement on cardiac magnetic resonance, suggesting covert CO-induced myocardial fibrosis. Myocardial damage can be evaluated using electrocardiography, echocardiography, computed tomography, and cardiac magnetic resonance. This paper offers recommendations for cardiac evaluations based on our collective experience of managing >2,000 cases of acute CO poisoning with supporting information taken from peer-reviewed published reports on CO poisoning.

Rare Causes of Acute Coronary Syndrome: Carbon Monoxide Poisoning

Acute coronary syndrome (ACS) is a spectrum of clinical and paraclinical disorders arising from an imbalance of oxygen demand and supply to the myocardium. The most common cause is atherosclerosis; however, other rare causes such as carbon monoxide (CO) poisoning should be considered. Through tissue hypoxia and direct cell injury, CO poisoning can lead to a broad spectrum of cardiac disorders, especially ACS. Materials and Methods. We have conducted a retrospective study in the Toxicology Department of Saint Spiridon Emergency University Hospital, including all patients admitted through the emergency department with CO poisoning. We divided the cohort into event group (myocardial injury) and non-event group (patients without myocardial injury) and performed a subset analysis of the former. Results. A total of 65 patients were included, 22 in the event and 43 in the non-event group. The severity of poisoning did not correlate with myocardial injury; however, 50% of the event group had severe poisoning with carboxyhaemoglobin ≥ 20%. Cardiac enzyme markers (troponin and creatin-kinase MB) had a statistically significant increase in the event group compared to the non-event group (p < 0.05). Most of the patients in the STEMI (50%) and NSTEMI (66.7%) groups had severe CO intoxication. The STEMI group had a mean age of 27.7 years old and no comorbidities. Conclusions. Myocardial injury can develop in CO poisoning irrespective of the severity of poisoning, and it can be transient, reversible, or permanent. Our study introduces new information on adverse cardiac events in patients with CO poisoning, focusing on the ACS. We found that the severity of CO poisoning plays an important role in developing myocardial injury, as 50% of patients in the event group were severely intoxicated. While in-hospital mortality in our study was low, further prospective studies should investigate the long-term mortality in these patients.