Editorial to “Electrocardiography on admission is associated with poor outcomes in coronavirus disease 2019 (COVID‐19) patients: A systematic review and meta‐analysis”

The global crisis due to coronavirus disease 2019 (COVID‐19) has caused more than hundred million infections and over 3 000 000 deaths. ¹ The disease is caused by the severe acute respiratory coronavirus 2 (SARS‐CoV‐2). While lung injury and systemic inflammation are main viral disease pathogenesis, myocardial injury is frequent among patients hospitalized with COVID‐19 and is associated with a poor prognosis. ² Possible mechanisms accounting for myocardial injury included the inhibition of myocardial angiotensin‐converting enzyme 2 (ACE2) expression after SARS‐CoV infection and systemic cytokine storm. ²

Although numerous modalities can be used for assessing myocardial injury in the patients with COVID‐19, electrocardiography (ECG) is ubiquitous, time‐saving, and easy‐to‐perform. The examination time of 12 lead‐surface ECG is 5 to 10 minutes, which is shorter than that by echocardiography, computed tomography, or magnetic resonance image. Remote ECG monitoring by mobile or portable device is feasible. Therefore, physical contact could be reduced to avoid cross‐infection. Characteristic ECG manifestations, suggestive of myocardial involvement, predict disease severity and future death. ³ , ⁴ ECG is also an important tool to monitor QT intervals as some of therapeutic drugs would prolong QT intervals and increase arrhythmia vulnerability. These make ECG a better tool and active research field to screen cardiac injury or risk stratification in the patients with COVID‐19.

In this issue of the journal, Alsagaff et al conducted a systematic review and meta‐analysis to appraise the latest evidence of the correlation between ECG on admission and clinical outcomes, including intensive care unit (ICU) admission, severe illness, and mortality in COVID‐19 patients. ⁵ This work consisted of seven studies with a total of 2539 patients. ⁵ The results revealed that characteristic ECG features on admission were associated with poor clinical outcomes. These ECG features encompassed the longer QTc interval (weighted means difference, WMD: 6.04), a prolonged QTc interval (more than 460‐500 ms, relative risks, RR: 1.89), longer QRS duration (WMD: 2.03), faster heart rate (WMD: 5.96), higher incidence of LBBB (RR: 2.55), premature atrial contraction (RR: 1.94), premature ventricular contraction (RR: 1.84), T‐wave inversion (RR: 1.68), and ST‐depression (RR: 1.61). In brief, ECGs on admission can be used for risk stratification of COVID‐19 patients and should be closely monitored in the hospitalized patients. ⁵

The present work re‐affirmed that the value of ECG abnormality on admission could be used as an early biomarker of poor clinical outcomes. These ECG features might not only be applied as alerting signs but also a potential tool for risk stratification to guide necessary treatment. To be noted, it is not clear whether these ECG features were the manifestation of the patients' pre‐existing comorbidities, the consequence of secondary hemodynamic changes (hypoxia, electrolytes imbalance, or acidosis), or direct cardiac involvement from COVID‐19. The differentiation between these pathologies might lead to different treatment strategies. Although numerous ECG changes have been linked to clinical outcomes in the patients with COVID‐19 in the present work, these features are also common risky ECG features for adverse cardiovascular events. The development of a specific ECG feature that links to direct cardiac involvement of COVID‐19 might be important to guide COVID‐19‐related cardiac therapy. Meanwhile, these ECG features are very non‐specific. Therefore, a significant number of the patients might be considered risky, subjected to overtreatment, and inadequately increase workload of medical staff. The incorporation of the risky ECG features and other cardiac biomarkers such as brain natriuretic peptide as the scoring system might be a better fit to guide clinical treatment of cardiac involvement. The present review mainly analyzed the data from 12 lead surface ECG. As COVID‐19 is highly contagious, the translation of these 12 lead ECG findings to real‐time monitoring by artificial intelligence‐assisted portable or mobile device will lead to future transformation of patient care in COVID‐19.

Nonetheless, there are still several limitations in this study. First, due to retrospective study design, the inter‐study heterogeneity was the main drawback, leading to insufficiently matched or adjusted confounders. Second, each study in the meta‐analysis stated different cut‐off values for a prolonged QTc interval. Moreover, Bazett's formula used in most studies may cause over‐correction of QTc interval at higher heart rates, which might over‐exaggerate the predictive impact on poor clinical outcomes. ⁵ Only ECGs on admission are reviewed, and however, dynamic change of ECGs during serial follow‐up or monitoring through disease progress of COVID‐19 might be also important to determine disease status and improve their clinical outcomes. In summary, Alsagaff et al should be congratulated on their timely review to summarize clinical relevance of ECGs in the patients with COVID‐19. ECGs on admission could provide prompt and crucial data for risk stratification and guide the treatment in the COVID‐19 patients.

CONFLICT OF INTEREST

The authors declare no conflict of interests for this article.

Cheng W‐H, Hu Y‐F, Chen S‐A. Editorial to “Electrocardiography on admission is associated with poor outcomes in coronavirus disease 2019 (COVID‐19) patients: A systematic review and meta‐analysis”. J Arrhythmia. 2021;37:886–887. 10.1002/joa3.12587

DATA AVAILABILITY STATEMENT

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