Predicting QT interval prolongation in patients diagnosed with the 2019 novel coronavirus infection

INTRODUCTION: 2019 novel coronavirus (COVID‐19) patients frequently develop QT interval prolongation that predisposes them to Torsades de Pointes and sudden cardiac death. Continuous cardiac monitoring has been recommended for any COVID‐19 patient with a Tisdale Score of seven or more. This recommendation, however, has not been validated. METHODS: We included 178 COVID‐19 patients admitted to a non‐intensive care unit setting of a tertiary academic medical center. A receiver operating characteristics curve was plotted to determine the accuracy of the Tisdale Score to predict QT interval prolongation. Multivariable analysis was performed to identify additional predictors. RESULTS: The area under the curve of the Tisdale Score was 0.60 (CI 95%, 0.46–0.75). Using the cutoff of seven to stratify COVID‐19, patients had a sensitivity of 85.7% and a specificity of 7.6%. Risk factors independently associated with QT interval prolongation included a history of end‐stage renal disease (ESRD) (OR, 6.42; CI 95%, 1.28–32.13), QTc ≥450 ms on admission (OR, 5.90; CI 95%, 1.62–21.50), and serum potassium ≤3.5 mmol/L during hospitalization (OR, 4.97; CI 95%, 1.51–16.36). CONCLUSION: The Tisdale Score is not a useful tool to stratify hospitalized non‐critical COVID‐19 patients based on their risks of developing QT interval prolongation. Clinicians should initiate continuous cardiac monitoring for patients who present with a history of ESRD, QTc ≥450 ms on admission or serum potassium ≤3.5 mmol/L.