This article focuses on the change in the QT interval in a study conducted on 84 adult patients with SARS-CoV-2 infection who were being treated with Hydroxychloroquine/ Azithromycin combination.
QTc was prolonged between day 3 and 4 in 30% of patients with increased QTc by greater than 40ms. In 11% of patients QTc was increased > 500 ms.
This represented a high risk group for irregular rhythm.
Results of study
- The average time of ECG follow up post HCQ/AZ exposure was 4.3+/- 1.7 days.
- The OTc interval prolonged from a baseline of 435+/- 24 ms to a maximum value of 463 +/- 32 ms
- The maximum value occurred on day 3.6+/- 1.6 of therapy
- 11% of patients developed severe QTc prolongation of > 500ms. This increases risk of malignant arrhythmia and Sudden Cardiac Death.
- Development of ARF was a significant predictor of severe QTc prolongation.
- Patients treated with HCQ/AZ, QTc were prolonged significantly.
Patients treated with Hydroxychloroquine/ Azithromycin were observed to have an increase in QT interval on ECG. Patients on HCQ/ AZ combination should have regular ECG and QTc monitoring.
Reference Link : https://www.medrxiv.org/content/10.1101/2020.04.02.20047050v1