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Updated: Nov 26, 2025

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Published on: April 21, 2014
Disease Severity Affects Ventricular Repolarization Parameters in Patients With COVID-19
Mevlut Koc1, Hilmi Erdem Sumbul2, Erdinc Gulumsek2
1Adana Health Practice and Research Center - Department of Cardiology, Adana - Turquia.
Background:
There is no study evaluating the Tpeak-Tend (Tpe) interval, Tpe/QT ratio, and Tpe/QTc ratio to assess cardiac arrhythmias in patients with COVID-19.
Objective:
We aimed to examine whether there is a change in QT, QTc, Tpe interval, Tpe/QT ratio, and Tpe/QTc ratio in patients with COVID-19.
Methods:
The study included 90 patients with COVID-19 infection and 30 age-and-sex-matched healthy controls. QT, QTc, Tpe interval, Tpe/QT ratio, and Tpe/QTc ratio were measured. The participants included in the study were divided into the following 4 groups: healthy controls (group I), patients with COVID-19 without pneumonia (group II), patients with COVID-19 and mild pneumonia (group III), and patients with COVID-19 and severe pneumonia (group IV). Statistical significance was set at p < 0.05.
Results:
It was found that baseline heart rate, presence of hypertension and diabetes, white blood cell count, blood urea nitrogen, creatinine, potassium, aspartate aminotransferase, alanine aminotransferase, NT-proBNP, high sensitive C reactive protein, D-dimer, hs-cTnI, Tpe, Tpe/QT, and Tpe/QTc increased from group I to group IV, and they were significantly higher in all patients in group IV (p < 0.05). Systolic-diastolic blood pressure, hemoglobin, and calcium levels were found to be lowest in group IV and significantly lower than in other groups (< 0.05). QT and QTc intervals were similar between groups. It was determined that increased heart rate, calcium, D-dimer, NT-proBNP and hs-CRP levels were significantly related to Tpe, Tpe/QT, and Tpe/QTc.
Conclusions:
In patients with COVID-19 and severe pneumonia, Tpe, Tpe/QT ratio, and Tpe/QTc ratio, which are among ventricular repolarization parameters, were found to be increased, without prolonged QT and QTc intervals. In this study, we cannot definitively conclude that the ECG changes observed are directly related to COVID-19 infection or inflammation, but rather associated with severe COVID-19 scenarios, which might involve other causes of inflammation and comorbidities. (Arq Bras Cardiol. 2020; 115(5):907-913).
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