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Updated: May 10, 2026

In vitro Assessment of Myocardial Protection following Hypothermia-Preconditioning in a Human Cardiac Myocytes Model
Published on: October 27, 2020
The pattern of Tpeak-Tend and QT interval, and J wave during therapeutic hypothermia
Sun-Mi Kim1, Gyo-Seung Hwang1, Jin-Sun Park1
1Department of Cardiology, Ajou University School of Medicine, Suwon, South Korea.
Background And Purpose:
The electrocardiogram manifestations of hypothermia include J waves and prolongation of QT intervals. This study described changes in repolarization patterns during therapeutic hypothermia (TH).
Methods:
We measured the QTc and the interval from the peak to the end of the T wave (TpTe) from the V4 and V6 leads in 20 patients with TH. The TpTe was also expressed as a ratio to the duration of QT ([TpTe/QT]×100%), and to the corrected value for heart rate (TpTe/√RR).
Results:
The QTc became prolonged in all patients during TH. While the TpTe/√RR did not change, the ([TpTe/QTe]×100%] decreased significantly during TH. The J wave developed during TH in seven patients. With one patient, ventricular fibrillation occurred preceded by an abnormal J wave and prolonged TpTe during TH.
Conclusions:
QTc prolongation without TpTe increase or abnormal J wave may not be arrhythmogenic during TH.
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