Patterns of Arrhythmias and Conduction Block in COVID-19 Patients and Its Relation to Myocardial Injury Detected by Cardiac Magnetic Resonance

COVID-19 has been declared a global pandemic by the World Health Organization and is responsible for hundreds of thousands of deaths worldwide.

Early reports from China suggested an overall cardiac arrhythmia incidence of 17% in patients hospitalized for COVID-19. A higher arrhythmia rate (44%) was observed in patients with COVID-19 admitted to the intensive care unit (ICU). However, details of the type and burden of arrhythmias in this population have not been elucidated.

Myocardial injury is common in patients with COVID-19, accounting for 7%-23% of reported cases in Wuhan, China. Among COVID-related myocardial injury, etiologies vary and can include myocarditis, myocardial infarction, sepsis-related myocardial injury, and/or stress induced cardiomyopathy. Myocardial injury is associated with high risk of developing all types of arrhythmia including atrial fibrillation, supraventricular tachycardia, ventricular tachycardia, ventricular fibrillation, and variable degrees of heart block. Sudden cardiac death was also reported.

The pathophysiology of COVID-19-related myocarditis is a combination of direct viral injury and cardiac damage due to the host's immune response. Although the pathophysiology of arrhythmias is still speculative, clinicians should provide prompt monitoring and treatment. The long term impact of COVID-19 myocarditis remains unknown

Meanwhile, cardiac magnetic resonance (CMR) imaging is an integral test in the diagnosis of myocardial injury. It can safely be used as a first-line diagnostic tool in the workup of myocardial injury associated with COVID-19.