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Updated: Apr 5, 2026

Isolation of Human Atrial Myocytes for Simultaneous Measurements of Ca2+ Transients and Membrane Currents
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High Frequency of Early Repolarization and Brugada-Type Electrocardiograms in Hypercalcemia

Keiko Sonoda1, Hiroshi Watanabe1, Takashi Hisamatsu2,3,4

  • 1Department of Cardiovascular Biology and Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.

Annals of Noninvasive Electrocardiology : the Official Journal of the International Society for Holter and Noninvasive Electrocardiology, Inc
|August 12, 2015
PubMed

Insights

Hypercalcemia is linked to J point elevation on ECGs, a finding that may increase arrhythmia risk. This elevation often resolves as calcium levels normalize, suggesting a direct relationship.

Area of Science:

  • Cardiology
  • Clinical Electrophysiology
  • Endocrinology

Background:

  • J wave (early repolarization) is associated with increased risk of lethal arrhythmias and sudden death.
  • Hypercalcemia can cause J point and ST segment elevation, but this relationship is not well-studied.

Purpose of the Study:

  • To investigate the effects of hypercalcemia on J point elevation in electrocardiograms (ECGs).

Main Methods:

  • Compared ECG findings in 89 hypercalcemia patients versus 267 healthy controls.
  • Assessed the association between J point elevation and arrhythmia events in hypercalcemia patients.

Main Results:

  • Hypercalcemia patients had longer PR intervals and QRS durations, and shorter QT/corrected QT intervals.
  • J point elevation, conduction disorders, and ST-T abnormalities were more frequent in hypercalcemia patients.
  • J point elevation decreased to control levels after hypercalcemia resolution; no in-hospital arrhythmias occurred.

Conclusions:

  • Hypercalcemia is associated with J point elevation.
  • J point elevation in hypercalcemia appears reversible upon normalization of calcium levels.
Abstract

Keywords:
Brugada syndromeJ point elevationJ waveearly repolarizationhypercalcemia

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