Cardiac Autonomic Regulation and Repolarization During Acute Experimental Hypoglycemia in Type 2 Diabetes.
Diabetes
; 66(5): 1322-1333, 2017 05.
Article
em En
| MEDLINE
| ID: mdl-28137792
ABSTRACT
Hypoglycemia is associated with increased cardiovascular mortality in trials of intensive therapy in type 2 diabetes mellitus (T2DM). We previously observed an increase in arrhythmias during spontaneous prolonged hypoglycemia in patients with T2DM. We examined changes in cardiac autonomic function and repolarization during sustained experimental hypoglycemia. Twelve adults with T2DM and 11 age- and BMI-matched control participants without diabetes underwent paired hyperinsulinemic clamps separated by 4 weeks. Glucose was maintained at euglycemia (6.0 mmol/L) or hypoglycemia (2.5 mmol/L) for 1 h. Heart rate, blood pressure, and heart rate variability were assessed every 30 min and corrected QT intervals and T-wave morphology every 60 min. Heart rate initially increased in participants with T2DM but then fell toward baseline despite maintained hypoglycemia at 1 h accompanied by reactivation of vagal tone. In control participants, vagal tone remained depressed during sustained hypoglycemia. Participants with T2DM exhibited greater heterogeneity of repolarization during hypoglycemia as demonstrated by T-wave symmetry and principal component analysis ratio compared with control participants. Epinephrine levels during hypoglycemia were similar between groups. Cardiac autonomic regulation during hypoglycemia appears to be time dependent. Individuals with T2DM demonstrate greater repolarization abnormalities for a given hypoglycemic stimulus despite comparable sympathoadrenal responses. These mechanisms could contribute to arrhythmias during clinical hypoglycemic episodes.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Arritmias Cardíacas
/
Sistema Nervoso Autônomo
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Pressão Sanguínea
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Diabetes Mellitus Tipo 2
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Coração
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Frequência Cardíaca
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Hipoglicemia
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Hipoglicemiantes
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Insulina
Limite:
Adult
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Diabetes
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Reino Unido