Subject-specific profiles of QT/RR hysteresis.

@article{Malik2008SubjectspecificPO,
  title={Subject-specific profiles of QT/RR hysteresis.},
  author={Marek Malik and Katerina Hnatkova and Tom{\'a}{\vs} Novotn{\'y} and Georg Schmidt},
  journal={American journal of physiology. Heart and circulatory physiology},
  year={2008},
  volume={295 6},
  pages={
          H2356-63
        }
}
The time lag of the QT interval adaptation to heart rate changes (QT/RR hysteresis) was studied in 40 healthy subjects (18 females; mean age, 30.4+/-8.1 yr) with 3 separate daytime (>13 h) 12-lead electrocardiograms (ECG) in each subject. In each recording, 330 individual 10-s ECG segments were measured, including 100 segments preceded by 2 min of heart rate varying greater than +/-2 beats/min. Other segments were preceded by a stable heart rate. In segments preceded by variable rate, QT/RR… 
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