Written by Meghan Breed
ECG abnormalities seen in patients with COVID-19 are likely due to a combination of factors. Abnormalities most commonly include supraventricular tachycardias, specifically sinus tachycardia.
Why does this matter?
Some studies have shown that up to 90% of critically ill COVID-19 patients demonstrate at least one ECG abnormality; these abnormalities are associated with increased risk of in-hospital mortality and need for mechanical ventilation. ECG abnormalities may be caused by, “cytokine storm, hypoxic injury, electrolyte abnormalities, plaque rupture, coronary spasm, microthrombi, or direct endothelial or myocardial injury.”
What’s that rhythm?
Supraventricular tachycardias are caused by hypovolemia, hypoperfusion, hypoxia, elevated body temperature, pain and anxiety. Sinus tachycardia is the most commonly encountered rhythm followed by atrial fibrillation – both are independent predictors of illness severity, myocardial injury and poor outcomes in COVID-19. Malignant ventricular dysrhythmias are the result of QT prolonging medications, metabolic abnormalities, and myocardial inflammation. Monomorphic ventricular tachycardia is the most frequent of the ventricular arrhythmias encountered; however, both out-of-hospital and in-hospital cardiac arrests as a result of COVID-19 are more likely to present as PEA or asystole. Bradycardias and AV blocks are less commonly encountered; however, interval and axis abnormalities are seen. Special attention should be paid to the presence of RV strain as a result of multi-lobar pneumonia or pulmonary embolism. Findings consistent with RV strain include right axis deviation with prominent R waves in leads V1 and V2 and ST depression/T wave inversions in leads II, III, aVF and V1 to V4. Morphologic presentations such as ST segment elevation/depression, T wave inversion and pathologic Q waves may be present due to myocardial injury associated with COVID-19 and, importantly, must be distinguished from acute myocardial infarction.
Electrocardiographic manifestations of COVID-19. Am J Emerg Med. 2020 Dec 29;41:96-103. doi: 10.1016/j.ajem.2020.12.060. Online ahead of print.