key: cord-0860603-gxucn4d8
authors: Ajmal, Muhammad; Butt, Khurrum; Moukabary, Talal
title: COVID-19 Disease and its Electrocardiographic Manifestations: Our Experience
date: 2021-04-16
journal: Am J Med
DOI: 10.1016/j.amjmed.2021.03.030
sha: 1a28be43e400bd094ad8f962b3a433f26a3837d0
doc_id: 860603
cord_uid: gxucn4d8

nan

Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) responsible for the recent pandemic is clinically manifested as Coronavirus Disease 2019 . Although COVID-19 has a predominant effect on the respiratory system, it also has deleterious impacts on other organs especially cardiovascular system [1] . Cardiovascular manifestations of COVID-19 include cardiac arrhythmias, heart failure, cardiomyopathy, myocarditis, cardiac injury, myocardial infarction, cardiogenic shock and venous thromboembolism [2] . We are writing this letter to highlight our experience about the effect of COVID-19 on electrocardiogram (ECG) observed at an academic center. Apart from the obvious ECG findings of arrhythmias, ST elevation myocardial infarction etc. in COVID-19 patients, we have noticed 3 different patterns of ECG in three different categories of COVID-19 disease.

Category 1 includes COVID-19 patients with a mild disease and symptoms are mostly cough, fatigue and low-grade fever without imaging evidence of pneumonia. These patients are stable and managed on the medical floors or at home. Electrocardiogram in mild disease is usually benign and may show sinus tachycardia as is shown in figure 1 . Sinus tachycardia is likely the compensatory response of the body to the mild febrile illness. These patients carry a good prognosis if they remain mildly symptomatic without developing pneumonia.

Category 2 includes patients in whom there is evidence of COVID-19 pneumonia and these patients are sicker and are managed usually in the intensive care unit. The ECG in this group of patients usually shows the pattern of ST elevation in lead III/aVF and V1 along with S1Q3 morphology in lead I and lead III. This is likely due to the rightward vector shift in the frontal plane as a result of right ventricular volume or pressure overload due to COVID pneumonia and is shown in figure 2 . Although in patients with venous pulmonary embolism the S1Q3T3 pattern is observed in lead I and lead III but when COVID-19 pneumonia has coexisting venous pulmonary embolism the ECG in these patients can show a pattern of ST elevation in lead III/aVF and V1 along with S1Q3 morphology in lead I and lead III as is shown in figure 3 . Searching the medical literature we found this pattern has been reported before and portends a bad prognosis and is also a predictor of cardiac arrest in patients with pulmonary disease [3] .

Category 3 includes patients with evidence of myocarditis along with COVID-19 pneumonia and in our experience this category has the worst prognosis. The ECG in this group shows diffuse ST segment elevation with a prolonged QTc interval. The diffuse ST elevation is likely due to involvement of left ventricle in myocarditis and does not have localization to coronary distribution. The ECG shown in figure  4 shows precordial and inferior leads ST elevation with hyperacute T waves and this patient had nonobstructive coronary artery disease on coronary angiography and cardiac magnetic resonance imaging demonstrated myocarditis.

There are also other potential mechanisms of QTc prolongation in COVID-19 patients possibly due to inflammation and drugs. The interleukin-6 was observed to block the rapid inward rectifying channel (IKr) by inhibiting the hERG (Ether-à-go-go Related Gene; alternative nomenclature KCNH2) leading to. prolonged QTc interval [4, 5] . The same mechanism of IKR blockade is also reported in drugs induced QTc prolongation and in COVID-19 patients the use of hydroxychloroquine and azithromycin along with other drugs prolong the QTc interval probably by this mechanism [6] .

In short, we report that various severities of COVID-19 disease have different presentations on the surface ECG. COVID-19 disease without pneumonia causes sinus tachycardia while COVID-19 pneumonia causes rightward vector shift on the surface ECG and of ST elevation in lead III/aVF and V1 along with S1Q3 morphology in lead I and lead III. The myocarditis which causes the diffuse ST elevation and prolonged QTc interval on ECG has the worst prognosis in our experience.

COVID-19 and cardiovascular diseases

Cardiovascular disease and COVID-19

Electrocardiographic right ventricular strain precedes hypoxic pulseless electrical activity cardiac arrests: Looking beyond pulmonary embolism. Resuscitation

Interleukin-6 inhibition of hERG underlies risk for acquired long QT in cardiac and systemic inflammation

COVID-19 Management and Arrhythmia: Risks and Challenges for Clinicians Treating Patients Affected by SARS-CoV-2. Front Cardiovasc Med

QT prolongation through hERG K(+) channel blockade: current knowledge and strategies for the early prediction during drug development