Investigating the Short‐Term Changes of the Electrocardiogram Indicators During Hospitalization in Patients With COVID‐19 Following the Use of Tocilizumab
Mahdi Zahedi, Golnaz Houshmand, Tabassom HosseiniABSTRACT
Objectives
To evaluate short‐term changes in electrocardiographic (ECG) parameters after tocilizumab administration in COVID‐19 patients, considering the drug's role in treating severe cases and the involvement of IL‐6 in cardiovascular effects and ECG alterations.
Methods
In this retrospective study, we assessed cardiovascular and electrocardiographic parameters in PCR‐confirmed COVID‐19 patients who received tocilizumab. ECG variables were evaluated at two time points: 24 h before and 24 h after drug administration. All ECGs were verified by a supervisor, and demographic information was extracted from patient records.
Results
33 patients were included, of whom 36.4% were men. The patients' ages ranged from 37 to 79 years. The corrected QT interval (QTc) measured 24 h before (QTc1) and 24 h after (QTc2) tocilizumab administration showed no significant difference (QTc1: 390.3 ± 31.67 ms; QTc2: 392.73 ± 36.68 ms). No significant ECG changes were observed in the ST segment, ventricular fibrillation (VF), ventricular tachycardia (VT), or atrial fibrillation (AF). Four patients experienced cardiorespiratory arrest within 24 h after receiving tocilizumab.
Conclusion
Tocilizumab administration in critically ill COVID‐19 patients was not associated with significant short‐term ECG changes or specific cardiovascular complications. Although previous studies in inflammatory diseases such as rheumatoid arthritis have reported QTc shortening following tocilizumab treatment, likely through suppression of IL‐6‐mediated systemic inflammation, no significant QTc reduction was observed in our cohort during the 24‐h follow‐up period. A few cases of cardiorespiratory arrest occurred; a causal relationship with tocilizumab could not be established due to the severity of illness and limited clinical data.