著者

Masao Yoshinaga Yumiko Ninomiya Yuji Tanaka Megumi Fukuyama Koichi Kato Seiko Ohno Minoru Horie Hiromitsu Ogata

出版者

The Japanese Circulation Society

雑誌

Circulation Journal (ISSN:13469843)

巻号頁・発行日

pp.CJ-23-0409, (Released:2023-12-01)

参考文献数

32

被引用文献数

1

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Background: This study was performed to clarify the clinical findings of pediatric patients diagnosed with long QT syndrome (LQTS) through electrocardiographic screening programs and to predict their outcome using Holter electrocardiographic approaches.Methods and Results: This retrospective study included pediatric patients with a Schwartz score of ≥3.5 who visited the National Hospital Organization Kagoshima Medical Center between April 2005 and March 2019. Resting 12-lead and Holter electrocardiograms were recorded at every visit. The maximum resting QTc and maximum Holter QTc values among all recordings were used for statistical analyses. To test the prognostic value of QTc for the appearance of cardiac events after the first hospital visit, receiver operating characteristic curves were used to calculate the area under the curve (AUC). Among 207 patients, 181 (87%) were diagnosed through screening programs. The prevalence of cardiac events after the first hospital visit was 4% (8/207). Among QTc at diagnosis, maximum resting QTc, and maximum Holter QTc, only maximum Holter QTc value was a predictor (P=0.02) of cardiac events after the hospital visit in multivariate regression analysis. The AUC of the maximum Holter QTc was significantly superior to that of maximum resting QTc.Conclusions: The maximum Holter QTc value can be used to predict the appearance of symptoms in pediatric patients with LQTS.

著者

Kanami Kojo Masao Yoshinaga Yu Kucho Daisuke Hazeki Yuji Tanaka Michiyo Mizota

出版者

日本不整脈学会

雑誌

Journal of Arrhythmia (ISSN:18804276)

巻号頁・発行日

vol.28, no.1, pp.61-64, 2012 (Released:2012-05-19)

参考文献数

8

被引用文献数

2

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Secondary long QT syndrome (LQTS) is caused by several drugs, cardiac conditions, and noncardiac conditions. One of the main metabolic causes is hypokalemia. We experienced treating a boy with secondary LQTS due to primary aldosteronism. The boy had been followed annually since he was 6 years old because his resting electrocardiogram (ECG) showed a prolonged QT interval. When he was 9 years old, he developed general fatigue and myalgia. The QT interval in his resting ECG became longer and serum data indicated rhabdomyolysis. The aldosterone level was high and renin activity was low. He was diagnosed with primary aldosteronism. When we, pediatricians, see children with LQTS, we are apt to think that their condition is congenital in nature. However, secondary or acquired LQTS should be always taken into consideration and be excluded not only in adults but also in the pediatric population.

著者

Daisuke Hazeki Masao Yoshinaga Hideto Takahashi Yuji Tanaka Yasue Haraguchi Mayumi Abe Masami Koga Toshiro Fukushige Masami Nagashima

出版者

日本循環器学会

雑誌

Circulation Journal (ISSN:13469843)

巻号頁・発行日

vol.74, no.8, pp.1663-1669, 2010 (Released:2010-07-23)

参考文献数

12

被引用文献数

13 33 8

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Background: The corrected QT interval (QTc) according to Bazett's formula (QTc = QT/RR1/2) has been used in clinical practice. Bazett's formula, however, overcorrects the QT interval at fast heart rates and undercorrects it at low heart rates. Guidelines and some investigators have recommended using Fridericia's formula (QTc = QT/RR1/3) in these cases, especially in tachycardic subjects. The aim of the present study was to determine cut-offs for QTc suitable for screening pediatric subjects with prolonged QT intervals, based on manually measured values corrected by Fridericia's formula in a large number of subjects. Methods and Results: Three consecutive QT and RR intervals were measured in 4,655, 4,655, and 5,273 1st, 7th, and 10th graders, aged 6, 12, and 15 years, respectively. Each QT interval was corrected by Fridericia's formula, and mean values were calculated. Determination of the cut-offs for screening was based on the prevalence of abnormal electrocardiographic phenotypes of 1:1,164 and on the upper 0.025 percentile in the QTc distribution derived from previous studies. The tentative cut-offs suitable for screening subjects with prolonged QT intervals were 430 ms for 1st graders, 445 ms for 7th graders, and 440 and 455 ms for 10th grade boys and girls, respectively. Conclusions: These tentative cut-offs can be used to screen subjects with prolonged QT intervals in the clinical setting. Further studies are needed to confirm their validity.  (Circ J 2010; 74: 1663 - 1669)

著者

Masao Yoshinaga Yoshiaki Kato Yuichi Nomura Daisuke Hazeki Toshiaki Yasuda Kazuhiro Takahashi Takashi Higaki Yuji Tanaka Akihiro Wada Hitoshi Horigome Hideto Takahashi Kentaro Ueno Hiroshi Suzuki Masami Nagashima

出版者

日本不整脈学会

雑誌

Journal of Arrhythmia (ISSN:18804276)

巻号頁・発行日

vol.27, no.3, pp.193-201, 2011-07-25 (Released:2011-08-26)

参考文献数

27

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Background: Electrocardiographic and molecular studies have clarified an association between sudden infant death syndrome (SIDS) and long QT syndrome (LQTS), and few data are available for the QT interval in infancy from birth to 1 year of age. Appropriate time of electrocardiographic screening is not clarified. Medical examinations during infancy are mandatory in Japan.Methods and Results: The study population included 1,058 infants. Electrocardiograms were collected with information of infants at birth and at examination. The QT intervals of three consecutive beats were measured in lead V5. Statistical analysis revealed that the following formula was appropriate to minimize the effect of heart rate for infants: corrected QT interval; QTc = QT interval/RR interval0.43. Subjects were divided into four groups as follows: 0–2, 3–6, 6–11, and 12–52 weeks of age. Tukey’s multiple comparison showed that the QTc intervals were longest (p<0.0001) in subjects who were 6–11 weeks of age.Conclusions: The QTc interval showed the highest peak at 6–11 weeks of age in infancy. The peak period of occurrence of SIDS is at approximately 2 months of age. An appropriate time of electrocardiographic screening for QT prolongation will be one month of age, and follow-up studies are needed.