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Published on: November 5, 2021
QTc interval prolongation in patients infected with SARS-CoV-2 and treated with antiviral drugs
Roger Esmel-Vilomara1, Paola Dolader1, Anna Sabaté-Rotes1
1Servicio de Cardiología Pediátrica, Hospital Universitario Vall d'Hebron, Barcelona, Spain.
Insights
Antiviral treatments for COVID-19 in children increased the QTc interval, with over a third experiencing prolonged QTc. Careful monitoring is essential, especially when using hydroxychloroquine, and treatment should be stopped if QTc exceeds 500ms.
Area of Science:
- Pediatric Cardiology
- Infectious Diseases
- Clinical Pharmacology
Background:
- Limited data exist on the cardiac safety of antiviral treatments for COVID-19 in pediatric populations.
- QTc prolongation is a significant adverse effect of some COVID-19 antivirals, necessitating pediatric-specific studies.
Purpose of the Study:
- To evaluate the impact of antiviral therapy on QTc interval in pediatric COVID-19 patients.
- To assess the incidence of QTc prolongation and associated arrhythmias in this cohort.
Main Methods:
- A case-control study matched pediatric COVID-19 patients receiving antivirals with uninfected controls (1:2 ratio).
- Electrocardiograms were analyzed prospectively at baseline, within 72 hours, and after 72 hours of treatment.
- Patients received hydroxychloroquine, lopinavir/ritonavir, or remdesivir.
Main Results:
- Over 22% of hospitalized pediatric COVID-19 patients received antiviral therapy, often with co-existing conditions like congenital heart disease.
- No significant difference in baseline QTc intervals was observed between cases and controls.
- A median QTc interval increase of 28.9ms was noted after 72 hours of treatment (P=.062), with 36.4% of patients exhibiting prolonged QTc, including 3 with QTc ≥500ms.
Conclusions:
- Antiviral use in pediatric COVID-19 patients can lead to QTc interval prolongation.
- While no arrhythmias were documented, active QTc monitoring is crucial during treatment with hydroxychloroquine and other antivirals.
- Discontinuation of treatment is recommended if QTc interval exceeds 500ms to mitigate risks.
Introduction:
Many antiviral agents, such as hydroxychloroquine, have been used to treat COVID-19, without being broadly accepted. QTc prolongation is a worrisome adverse effect, scarcely studied in pediatrics.
Patients And Methods:
Paediatric patients affected from COVID-19 who received antivirals were matched (1:2) with controls not infected nor exposed. Electrocardiograms were prospectively analyzed at baseline, during the first 72 h of treatment and after 72 h.
Results:
Eleven (22.9%) out of 48 patients admitted due to COVID-19 (March-July 2020) received antiviral therapy. All had underlying diseases: congenital heart disease (4/11; 36.4%) and immunosuppression (3/11; 27.3%) stand out. 5/11 (45.5%) received treatment at baseline with a potential effect on QTc. There where no differences observed in the baseline QTc between cases and controls: 414.8 ms (49.2) vs 416.5 ms (29.4), (P = .716). Baseline long QT was observed in 2/11 cases and 2/22. Among cases, 10/11 (90.9%) received hydroxychloroquine, mainly associated with azithromycin (8/11; 72.7%), 3 received lopinavir/ritonavir and one remdesivir. The median increase in QTc after 72 h under treatment was 28.9 ms [IQR 48.7] (P = .062). 4/11 (36.4%) patients had a long QTc at 72 h, resulting in 3 patients ≥500 ms; treatment was stopped in one (QTc 510 ms) but ventricular arrhythmias were not documented.
Conclusions:
The use of antivirals caused an increase on the QTc interval after 72 h of treatment, being the QTc long in 36.3% of the patients, although no arrhythmic events were observed. The use of hydroxychloroquine and antivirals requires active QTc monitoring and it is recommended to discontinue treatment if QTc > 500 ms.
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