Potential Causes of Sudden Cardiac Arrest in a Patient With Covid-19

Background: COVID-19-related arrhythmia may occur in up to 17% of cases.Torsade de Pointes has been reported as a rare but potentially life-threatening complication in COVID-19 patients.Yet, its mechanism of disease remained poorly understood.Case: A 67-year-old female with a history of depression, and hypothyroidism presented with shortness of breath.Upon ED arrival, she was diagnosed with COVID-19 pneumonia complicated with hypoxia (SpO2=74%).Later, she sustained a cardiac arrest due to ventricular fibrillation for which she was defibrillated and subsequently returned to spontaneous circulation.EKG revealed normal sinus rhythm, incomplete LBBB pattern, and prolonged QT interval (QTc =489 ms).Cardiac telemetry detected two episodes of polymorphic ventricular tachycardia (Torsades de Pointes -TdP) lasting for 6 seconds and 3 seconds, respectively.Yet, her hemodynamic was stable during those episodes with unremarkable lab results.CT angiogram showed no findings of pulmonary embolism.TTE displayed normal systolic function (LVEF 60%) without any structural abnormalities. Decision-making:The diagnosis of cardiac arrest secondary to TdP was made.Several possible mechanisms cause her QT prolongation, including QT-prolonging medications, electrolyte disturbances, cardiac injury associated with direct invasion of SARS-CoV-2, hyperinflammatory response, hypoxia or their synergistic effects.She was treated with IV magnesium, potassium repletion, and discontinuation of duloxetine and Zofran.Follow-up EKGs showed normalization of QTc. Conclusion:TdP may occur in COVID-19 patients and can progress to cardiac arrest.Appropriate identification and correction of potential causes as above and their synergistic effects could prevent malignant arrhythmia.