TY - JOUR
T1 - Cardiac repolarization during hypoglycaemia and hypoxaemia in healthy males
T2 - impact of renin-angiotensin system activity
AU - Due-Andersen, Rikke
AU - Høi-Hansen, Thomas
AU - Olsen, Niels Vidiendal
AU - Larroude, Charlotte Ellen
AU - Kanters, Jørgen Kim
AU - Boomsma, Frans
AU - Pedersen-Bjergaard, Ulrik
AU - Thorsteinsson, Birger
PY - 2008/2
Y1 - 2008/2
N2 - AIMS: Activity in the renin-angiotensin system (RAS) may influence the susceptibility to cardiac arrhythmia. To study the effect of basal RAS activity on cardiac repolarization during myocardial stress induced by hypoglycaemia or hypoxaemia in healthy humans.METHODS AND RESULTS: Ten subjects with high RAS activity and 10 subjects with low RAS activity were studied on three different occasions: (i) hypoglycaemia (nadir P-glucose 2.7 +/- 0.5 mmol/L), (ii) hypoxaemia (nadir pO(2) 5.8 +/- 0.5 kPa), and (iii) normoglycaemic normoxia (control day). QT parameters were registered by Holter monitoring. Hypoglycaemia and hypoxaemia induced QTc prolongation (P < 0.001, both stimuli). The QT/RR slope and the VR increased as a function of hypoglycaemia, but were unaffected by hypoxaemia. Low RAS activity was associated with a steeper QT/RR slope in the recovery phase after both stimuli: hypoglycaemia: P = 0.04; hypoxia: P = 0.03. RAS activity had no impact on QTc [P = 0.48 (hypoglycaemia) and P = 0.40 (hypoxaemia)] or any of the other outcome variables.CONCLUSION: Basal RAS activity has significant impact on QT dynamics, but not the corrected QT interval, during recovery from hypoglycaemia and hypoxaemia. The impact, however, is modest and more subtle than initially expected. The clinical relevance is unclear.
AB - AIMS: Activity in the renin-angiotensin system (RAS) may influence the susceptibility to cardiac arrhythmia. To study the effect of basal RAS activity on cardiac repolarization during myocardial stress induced by hypoglycaemia or hypoxaemia in healthy humans.METHODS AND RESULTS: Ten subjects with high RAS activity and 10 subjects with low RAS activity were studied on three different occasions: (i) hypoglycaemia (nadir P-glucose 2.7 +/- 0.5 mmol/L), (ii) hypoxaemia (nadir pO(2) 5.8 +/- 0.5 kPa), and (iii) normoglycaemic normoxia (control day). QT parameters were registered by Holter monitoring. Hypoglycaemia and hypoxaemia induced QTc prolongation (P < 0.001, both stimuli). The QT/RR slope and the VR increased as a function of hypoglycaemia, but were unaffected by hypoxaemia. Low RAS activity was associated with a steeper QT/RR slope in the recovery phase after both stimuli: hypoglycaemia: P = 0.04; hypoxia: P = 0.03. RAS activity had no impact on QTc [P = 0.48 (hypoglycaemia) and P = 0.40 (hypoxaemia)] or any of the other outcome variables.CONCLUSION: Basal RAS activity has significant impact on QT dynamics, but not the corrected QT interval, during recovery from hypoglycaemia and hypoxaemia. The impact, however, is modest and more subtle than initially expected. The clinical relevance is unclear.
KW - Adult
KW - Cross-Over Studies
KW - Electrocardiography, Ambulatory
KW - Humans
KW - Hypoglycemia
KW - Hypoxia
KW - Insulin
KW - Insulin, Regular, Pork
KW - Long QT Syndrome
KW - Male
KW - Oxygen Inhalation Therapy
KW - Renin-Angiotensin System
KW - Risk Factors
KW - Single-Blind Method
KW - Journal Article
KW - Randomized Controlled Trial
KW - Research Support, Non-U.S. Gov't
U2 - 10.1093/europace/eum286
DO - 10.1093/europace/eum286
M3 - Journal article
C2 - 18204042
SN - 1099-5129
VL - 10
SP - 219
EP - 226
JO - Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology
JF - Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology
IS - 2
ER -