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Electrocardiographic findings over time and their prognostic value in patients with COVID-19.

BACKGROUND
The objective of this study was to carry out a retrospective analysis of the progression of electrocardiographic (ECG) findings over time, based on biomarkers for myocardial injuries in patients with coronavirus disease 2019 (COVID-19). Also, the ECG observations were assessed for possible prognostic use.


METHODS
Diagnostic criteria provided by the Coronavirus Pneumonia Diagnosis and Treatment Program of the Chinese National Health Commission were used. We conducted a retrospective analysis of 31 COVID-19 cases diagnosed as positive by high-throughput sequencing of nasopharyngeal nucleic acid test and admitted to Sichuan Province Public Health Clinical Medical Center, Sichuan Province, China. Based on changes in biomarkers, the 31 participants were divided into a non-myocardial injury group (A) and a myocardial injury group (B). Our study observed the dynamic changes and new abnormal changes of the ECG during the hospitalization of patients.


RESULTS
The results summarized in the 4 following points: (I) the time sequence changes for ST and T indicated that the absolute ST-segment depression and T-wave inversion values in group B were larger. (II) The heart rate (HR) and RV5 values in group B were higher, the QTC value for group B was lower. (III) The sensitivity of ST-segment depression for the diagnosis of myocardial injury was 32.60% and the specificity was 90.50%. The sensitivity of T-wave inversion was 41.30% and the specificity was 85.10%. (IV) Lactate dehydrogenase (LDH) is a major factor affecting patient's death.


CONCLUSIONS
If abnormal ST-T, increased heart rate, shortened QTC interval, and high ventricular voltage are observed in a COVID-19 patient, it may infer that myocardial damage has occurred. Using ECG as a point of reference for change can compensate for the time limitation of myocardial enzyme index. Regardless of the stage of disease development, ECG can reflect myocardial damage. Particularly in the 8-12 days after hospitalization, almost all myocardial enzymes cannot be applied. The ST-depression and T-wave inversion had diagnostic significance with relatively high sensitivity and specificity for myocardial injury. Assessment of LDH and biomarkers in combination with ECG can more accurately reflect myocardial injury, and facilitate prompt clinical diagnosis and treatment.