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. 2008 Jun 9;31(6):270–274. doi: 10.1002/clc.20208

Assessment of QT Intervals and Prevalence of Short QT Syndrome in Japan

Akira Funada 1,✉, Kenshi Hayashi 1, Hidekazu Ino 1, Noboru Fujino 1, Katsuharu Uchiyama 1, Kenji Sakata 1, Eiichi Masuta 1, Yuichiro Sakamoto 1, Toshinari Tsubokawa 1, Masakazu Yamagishi 1
PMCID: PMC6653181  PMID: 18543308

Abstract

Background

Long QT syndrome causes ventricular tachyarrhythmias and sudden death. Recently, a short QT interval has also been shown to be associated with an increased risk of tachyarrhythmia and sudden death. However, the prevalence of short QT syndrome is not well‐known.

Hypothesis

The aim of this study was to assess the distribution of corrected QT intervals (QTc) and prevalence of short QT syndrome.

Methods

This study comprised 12,149 consecutive subjects who received a consultation at Kanazawa University Hospital, Kanazawa, Japan, and had an electrocardiogram (ECG) between February 2003 and May 2004. Of these subjects, 1,165 subjects were excluded because of inappropriate ECGs, while the remaining 10,984 subjects had their last‐recorded ECGs analyzed.

Results

The QTc values showed a nearly normal distribution (408 ± 25 msec1/2), and were significantly longer in females (412 ± 24 msec1/2) than in males (404 ± 25 msec1/2) (p < 0.05). Among 5,511 males, 69 subjects (1.25%) exhibited QTc < 354 msec1/2 (2 standard deviations [SDs] below the mean in males), and among 5,473 females, 89 subjects (1.63%) exhibited QTc < 364 msec1/2 (2 SDs below the mean in females). Only 3 subjects (0.03% in all subjects and 0.05% in males) exhibited QTc < 300 msec1/2, however, none had clinical symptoms of short QT syndrome.

Conclusions

Short QT syndrome may be very rare. Copyright © 2008 Wiley Periodicals, Inc.

Keywords: short QT interval, sex difference of QT intervals, electrocardiogram, sudden death, arrhythmia

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References

  • 1. Moss AJ, Schwartz PJ, Crampton RS, Tzivoni D, Locati EH, et al.: The long QT syndrome: prospective longitudinal study of 328 families. Circulation 1991; 84: 1136–1144. [DOI] [PubMed] [Google Scholar]
  • 2. Jervell A, Lange‐Nielsen F: Congenital deaf‐mutism, functional heart disease with prolongation of the QT interval and sudden death. Am Heart J 1957; 54: 59–68. [DOI] [PubMed] [Google Scholar]
  • 3. Romano C, Gemme G, Pongiglione R: Aritmie cardiache rare dell'eta pediatrica. Clin Pediatr 1963; 45: 656–683. [PubMed] [Google Scholar]
  • 4. Ward OC: A new familial cardiac syndrome in children. J Ir Med Assoc 1964; 54: 103–106. [PubMed] [Google Scholar]
  • 5. Gussak I, Brugada P, Brugada J, Wright RS, Kopecky SL, et al.: Idiopathic short QT interval a new clinical syndrome? Cardiology 2000; 94: 99–102. [DOI] [PubMed] [Google Scholar]
  • 6. Gaita F, Giustetto C, Bianchi F, Wolpert C, Schimpf R, et al.: Short QT syndrome: a familial cause of sudden death. Circulation 2003; 108: 965–970. [DOI] [PubMed] [Google Scholar]
  • 7. Goldberger AL. Electrocardiograhy In: Braunwald E: ed. Harrison's Principles of Internal Medicine 15th ed. New York: Mcgraw‐Hill; 2001; 1262–1271. [Google Scholar]
  • 8. Bazett HC: An analysis of the time‐relations of electrocardiograms. Heart 1920; 7: 353–370. [Google Scholar]
  • 9. Rautaharju PM, Zhou SH, Wong S, Calhoun HP, Berenson GS, et al.: Sex differences in the evolution of the electrocardiographic QT intervals with age. Can J Cardiol 1992; 8: 690–695. [PubMed] [Google Scholar]
  • 10. Nierenberg DW, Ransil BJ: Q‐aTc interval as a clinical indicator of hypercalcemia. Am J Cardiol 1979; 44: 243–248. [DOI] [PubMed] [Google Scholar]
  • 11. Nakagawa M, Takahashi N, Iwao T, Yonemochi H, Ooie T, et al.: Evaluation of autonomic influences on QT dispersion using the head‐up tilt test in healthy subjects. Pacing Clin Electrophysiol 1999; 22: 1158–1163. [DOI] [PubMed] [Google Scholar]
  • 12. DiFrancesco D, Ducouret P, Robinson RB: Muscarinic modulation of the cardiac rate at low acetylcholine concentrations. Science 1989; 243: 669–671. [DOI] [PubMed] [Google Scholar]
  • 13. Cheng TO: Digitalis administration: an underappreciated but common cause of short QT interval. Circulation 2004; 109: e152. [DOI] [PubMed] [Google Scholar]
  • 14. Algra A, Tijssen JG, Roelandt JR, Pool J, Lubsen J: QT interval variables from 24‐hour electrocardiography and the 2‐y risk of sudden death. Br Heart J 1993; 70: 43–48. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 15. Brugada R, Hong K, Dumaine R, Cordeiro JM, Gaita F, et al.: Sudden death associated with short QT syndrome linked to mutations in HERG. Circulation 2004; 109: 30–35. [DOI] [PubMed] [Google Scholar]
  • 16. Bellocq C, van Ginneken A, Bezzina CR, Alders M, Escaude D, et al.: Mutation in the KCNQ1 gene leading to the short QT‐interval syndrome. Circulation 2004; 109: 2394–2397. [DOI] [PubMed] [Google Scholar]
  • 17. Priori SG, Pandit SV, Rivolta I, Berenfeil O, Ronchetti E, et al.: A novel form of short QT syndrome (SQTS3) is caused by a mutation in the KCNJ2 gene. Circ Res 2005; 96: 800–807. [DOI] [PubMed] [Google Scholar]
  • 18. Roden DM, Lazzara R, Rosen M, Schwarts PJ, Towbin J, et al.: Multiple mechanisms in the long‐QT syndrome: current knowledge, gaps, and future directions. The SADS Foundation Task Force on LQTS. Circulation 1996; 94: 1996–2012. [DOI] [PubMed] [Google Scholar]
  • 19. Laetitia G, Chloe B, Myram B, Franck P, Sophie D, et al.: New KCNQ1 mutations leading to haploinsufficiency in a general population: defective trafficking of a KvLQT1 mutant. Cardiovasc Res 2004; 63: 60–68. [DOI] [PubMed] [Google Scholar]
  • 20. Simonson E, Cady LD, Woodbury M: The normal Q‐T interval. Am Heart J 1962; 63: 747–753. [DOI] [PubMed] [Google Scholar]
  • 21. Lepeschkin E: Components of Q‐T and Q‐U intervals of the electrocardiogram in normals. J Appl Physiol 1956; 9: 443–446. [DOI] [PubMed] [Google Scholar]

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