TY - JOUR
T1 - Variability of Myocardial Repolarization in Pediatric Patients with a Ventricular Septal Defect
AU - Uchida, Hidetoshi
AU - Nishio, Miki
AU - Omeki, Yumi
AU - Takeuchi, Yuka
AU - Nagata, Rina
AU - Oikawa, Shota
AU - Nagatani, Arisa
AU - Eryu, Yoshihiko
AU - Hata, Tadayoshi
AU - Yoshikawa, Tetsushi
N1 - Publisher Copyright:
© 2016, Springer Science+Business Media New York.
PY - 2016/12/1
Y1 - 2016/12/1
N2 - In patients with a ventricular septal defect, left-to-right shunting increases the left ventricular preload. This pathological change affects myocardial depolarization and repolarization and has the potential to evoke arrhythmogenic substrates. We examined the effect of ventricular septal defects on myocardial repolarization by investigating the variability in the repolarization interval. This retrospective study included 19 patients (mean age, 1.8 ± 2.1 years) who underwent surgical closure (mean left-to-right shunt ratio, 2.60 ± 0.55) and 26 age-matched healthy controls from 2008 to 2015. Using preoperative electrocardiograms, we studied two electrocardiographic parameters (heart rate-corrected repolarization and variability of repolarization) and four repolarization intervals (QT, JT, J point to T peak [JTp], and T peak to T end [Tp-e] intervals). The variability index (VI) was calculated from the logarithm of the ratio of the repolarization parameter variance to heart rate variance. The various measures were compared between the patients and controls, and significant differences were found in the corrected QT, JTp, and Tp-e intervals (p < 0.05). The VI of the four intervals also showed significant differences (patients vs. controls: QTVI, −0.55 ± 0.61 vs. −1.10 ± 0.53; JTVI, −0.33 ± 0.60 vs. −0.86 ± 0.57; JTpVI, −0.15 ± 0.78 vs. −0.73 ± 0.56; Tp-eVI, 0.75 ± 0.70 vs. 0.11 ± 0.73, respectively; p < 0.05). No correlation was found between the QTVI and corrected QT interval using linear regression analysis. These repolarization characteristics provide not only electrophysiological indices but also a new index with which to assess the pathophysiology of congenital heart disease.
AB - In patients with a ventricular septal defect, left-to-right shunting increases the left ventricular preload. This pathological change affects myocardial depolarization and repolarization and has the potential to evoke arrhythmogenic substrates. We examined the effect of ventricular septal defects on myocardial repolarization by investigating the variability in the repolarization interval. This retrospective study included 19 patients (mean age, 1.8 ± 2.1 years) who underwent surgical closure (mean left-to-right shunt ratio, 2.60 ± 0.55) and 26 age-matched healthy controls from 2008 to 2015. Using preoperative electrocardiograms, we studied two electrocardiographic parameters (heart rate-corrected repolarization and variability of repolarization) and four repolarization intervals (QT, JT, J point to T peak [JTp], and T peak to T end [Tp-e] intervals). The variability index (VI) was calculated from the logarithm of the ratio of the repolarization parameter variance to heart rate variance. The various measures were compared between the patients and controls, and significant differences were found in the corrected QT, JTp, and Tp-e intervals (p < 0.05). The VI of the four intervals also showed significant differences (patients vs. controls: QTVI, −0.55 ± 0.61 vs. −1.10 ± 0.53; JTVI, −0.33 ± 0.60 vs. −0.86 ± 0.57; JTpVI, −0.15 ± 0.78 vs. −0.73 ± 0.56; Tp-eVI, 0.75 ± 0.70 vs. 0.11 ± 0.73, respectively; p < 0.05). No correlation was found between the QTVI and corrected QT interval using linear regression analysis. These repolarization characteristics provide not only electrophysiological indices but also a new index with which to assess the pathophysiology of congenital heart disease.
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U2 - 10.1007/s00246-016-1457-9
DO - 10.1007/s00246-016-1457-9
M3 - Article
C2 - 27554253
AN - SCOPUS:84983418472
SN - 0172-0643
VL - 37
SP - 1458
EP - 1464
JO - Pediatric Cardiology
JF - Pediatric Cardiology
IS - 8
ER -