Audrey Dionne1, Anne Fournier1, Nagib Dahdah1, Dominic Abrams2, Paul Khairy3, Sylvia Abadir4. 1. Division of Cardiology, CHU mère-enfant Sainte-Justine, Université de Montréal, Montréal, Québec, Canada. 2. Electrophysiology Service, Boston Children's Hospital, Harvard University, Boston, MA, USA. 3. Division of Cardiology, CHU mère-enfant Sainte-Justine, Université de Montréal, Montréal, Québec, Canada; Electrophysiology Service and Adult Congenital Heart Center, Montreal Heart Institute, Université de Montréal, Montréal, Québec, Canada. 4. Division of Cardiology, CHU mère-enfant Sainte-Justine, Université de Montréal, Montréal, Québec, Canada; Electrophysiology Service and Adult Congenital Heart Center, Montreal Heart Institute, Université de Montréal, Montréal, Québec, Canada. Electronic address: sylvia.abadir@gmail.com.
Abstract
BACKGROUND: QT-interval variations in response to exercise-induced increases in heart rate have been reported in children and adults in the diagnosis of long QT syndrome (LQTS). A quick standing challenge has been proposed as an alternative provocative test in adults, with no pediatric data yet available. METHODS: A standing test was performed in 100 healthy children (mean age, 9.7 ± 3.1 years) after 10 minutes in a supine position with continuous electrocardiographic recording. QT intervals were measured at baseline, at maximal heart rate, at maximal QT, and at each minute of a 5-minute recovery while standing. Measurements were taken in leads II/V5 and were corrected for heart rate (QTc). RESULTS: On standing, the heart rate increased by 29 ± 10 beats per minute (bpm). The QT interval was similar at baseline and on standing (394 ± 34 ms vs 394 ± 34 ms; P = 1.0). However, QTc increased from 426 ± 21 to 509 ± 41 ms (P < 0.001). The 95th percentile for QTc at baseline and maximal heart rate was 457 ms and 563 ms, respectively. At 1 minute of recovery, the QT interval was shorter (375 ± 31 ms) compared with baseline (394 ± 34 ms; P < 0.001) and standing (394 ± 34 ms; P < 0.001). QTc reached baseline values after 1 minute of recovery and remained stable thereafter (423 ± 23 ms at 1 minute; 426 ± 22 ms at 5 minutes; P = 1.0). CONCLUSIONS: This first characterization of QTc changes on standing in children shows substantial alterations, which are greater than those seen in adults. Two-thirds of the children would have been misclassified as having LQTS by adult criteria, indicating the need to create child-specific standards.
BACKGROUND: QT-interval variations in response to exercise-induced increases in heart rate have been reported in children and adults in the diagnosis of long QT syndrome (LQTS). A quick standing challenge has been proposed as an alternative provocative test in adults, with no pediatric data yet available. METHODS: A standing test was performed in 100 healthy children (mean age, 9.7 ± 3.1 years) after 10 minutes in a supine position with continuous electrocardiographic recording. QT intervals were measured at baseline, at maximal heart rate, at maximal QT, and at each minute of a 5-minute recovery while standing. Measurements were taken in leads II/V5 and were corrected for heart rate (QTc). RESULTS: On standing, the heart rate increased by 29 ± 10 beats per minute (bpm). The QT interval was similar at baseline and on standing (394 ± 34 ms vs 394 ± 34 ms; P = 1.0). However, QTc increased from 426 ± 21 to 509 ± 41 ms (P < 0.001). The 95th percentile for QTc at baseline and maximal heart rate was 457 ms and 563 ms, respectively. At 1 minute of recovery, the QT interval was shorter (375 ± 31 ms) compared with baseline (394 ± 34 ms; P < 0.001) and standing (394 ± 34 ms; P < 0.001). QTc reached baseline values after 1 minute of recovery and remained stable thereafter (423 ± 23 ms at 1 minute; 426 ± 22 ms at 5 minutes; P = 1.0). CONCLUSIONS: This first characterization of QTc changes on standing in children shows substantial alterations, which are greater than those seen in adults. Two-thirds of the children would have been misclassified as having LQTS by adult criteria, indicating the need to create child-specific standards.
Authors: Martin K Stiles; Arthur A M Wilde; Dominic J Abrams; Michael J Ackerman; Christine M Albert; Elijah R Behr; Sumeet S Chugh; Martina C Cornel; Karen Gardner; Jodie Ingles; Cynthia A James; Jyh-Ming Jimmy Juang; Stefan Kääb; Elizabeth S Kaufman; Andrew D Krahn; Steven A Lubitz; Heather MacLeod; Carlos A Morillo; Koonlawee Nademanee; Vincent Probst; Elizabeth V Saarel; Luciana Sacilotto; Christopher Semsarian; Mary N Sheppard; Wataru Shimizu; Jonathan R Skinner; Jacob Tfelt-Hansen; Dao Wu Wang Journal: Heart Rhythm Date: 2020-10-19 Impact factor: 6.343
Authors: Martin K Stiles; Arthur A M Wilde; Dominic J Abrams; Michael J Ackerman; Christine M Albert; Elijah R Behr; Sumeet S Chugh; Martina C Cornel; Karen Gardner; Jodie Ingles; Cynthia A James; Jyh-Ming Jimmy Juang; Stefan Kääb; Elizabeth S Kaufman; Andrew D Krahn; Steven A Lubitz; Heather MacLeod; Carlos A Morillo; Koonlawee Nademanee; Vincent Probst; Elizabeth V Saarel; Luciana Sacilotto; Christopher Semsarian; Mary N Sheppard; Wataru Shimizu; Jonathan R Skinner; Jacob Tfelt-Hansen; Dao Wu Wang Journal: J Arrhythm Date: 2021-04-08
Authors: Arja S Vink; Ben J M Hermans; Joana Pimenta; Puck J Peltenburg; Luc H P M Filippini; Nynke Hofman; Sally-Ann B Clur; Nico A Blom; Arthur A M Wilde; Tammo Delhaas; Pieter G Postema Journal: Heart Rhythm O2 Date: 2021-03-13
Authors: Neha Mantri; Meng Lu; Jonathan G Zaroff; Neil Risch; Thomas Hoffmann; Akinyemi Oni-Orisan; Catherine Lee; Eric Jorgenson; Carlos Iribarren Journal: J Am Heart Assoc Date: 2021-09-28 Impact factor: 5.501