Glucose ingestion causes cardiac repolarization disturbances in type 1 long QT syndrome patients and healthy subjects

TY - JOUR

T1 - Glucose ingestion causes cardiac repolarization disturbances in type 1 long QT syndrome patients and healthy subjects

AU - Hyltén-Cavallius, Louise

AU - Iepsen, Eva W

AU - Christiansen, Michael

AU - Graff, Claus

AU - Linneberg, Allan

AU - Pedersen, Oluf

AU - Holst, Jens J

AU - Hansen, Torben

AU - Torekov, Signe S

AU - Kanters, Jørgen K

N1 - Copyright © 2017 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

PY - 2017/8

Y1 - 2017/8

N2 - Background Both hypoglycemia and severe hyperglycemia constitute known risk factors for cardiac repolarization changes potentially leading to malignant arrhythmias. Patients with loss of function mutations in KCNQ1 are characterized by long QT syndrome (LQTS) and may be at increased risk for glucose-induced repolarization disturbances. Objective The purpose of this study was to test the hypothesis that KCNQ1 LQTS patients are at particular risk for cardiac repolarization changes during the relative hyperglycemia that occurs after an oral glucose load. Methods Fourteen KCNQ1 LQTS patients and 28 control participants matched for gender, body mass index, and age underwent a 3-hour oral 75-g glucose tolerance test with ECGs obtained at 7 time points. Fridericia corrected QT interval (QTcF), Bazett corrected QT interval (QTcB), and the Morphology Combination Score (MCS) were calculated. Results QTc and MCS increased in both groups. MCS remained elevated until 150 minutes after glucose ingestion, and the maximal change from baseline was larger among KCNQ1 LQTS patients compared with control subjects (0.28 ± 0.27 vs 0.15 ± 0.13; P <.05). Conclusion Relative hyperglycemia induced by ingestion of 75-g glucose caused cardiac repolarization disturbances that were more severe in KCNQ1 LQTS patients compared with control subjects.

AB - Background Both hypoglycemia and severe hyperglycemia constitute known risk factors for cardiac repolarization changes potentially leading to malignant arrhythmias. Patients with loss of function mutations in KCNQ1 are characterized by long QT syndrome (LQTS) and may be at increased risk for glucose-induced repolarization disturbances. Objective The purpose of this study was to test the hypothesis that KCNQ1 LQTS patients are at particular risk for cardiac repolarization changes during the relative hyperglycemia that occurs after an oral glucose load. Methods Fourteen KCNQ1 LQTS patients and 28 control participants matched for gender, body mass index, and age underwent a 3-hour oral 75-g glucose tolerance test with ECGs obtained at 7 time points. Fridericia corrected QT interval (QTcF), Bazett corrected QT interval (QTcB), and the Morphology Combination Score (MCS) were calculated. Results QTc and MCS increased in both groups. MCS remained elevated until 150 minutes after glucose ingestion, and the maximal change from baseline was larger among KCNQ1 LQTS patients compared with control subjects (0.28 ± 0.27 vs 0.15 ± 0.13; P <.05). Conclusion Relative hyperglycemia induced by ingestion of 75-g glucose caused cardiac repolarization disturbances that were more severe in KCNQ1 LQTS patients compared with control subjects.

KW - Journal Article

U2 - 10.1016/j.hrthm.2017.04.018

DO - 10.1016/j.hrthm.2017.04.018

M3 - Journal article

C2 - 28400316

SN - 1547-5271

VL - 14

SP - 1165

EP - 1170

JO - Heart Rhythm

JF - Heart Rhythm

IS - 8

ER -