Regulation of QT indices mediated by autonomic nervous function in patients with type 2 diabetes.
Int J Cardiol
; 96(3): 375-9, 2004 Sep.
Article
em En
| MEDLINE
| ID: mdl-15301890
ABSTRACT
Both the QT interval and QT dispersion in diabetic patients have been reported to increase with the progression of cardiac autonomic neuropathy and to have a prognostic value. We assessed the cardiac autonomic influences on QT indices using the measurements of baroreflex sensitivity, heart rate variability, and cardiac (123)I-metaiodobenzylguanidine scintigraphic findings in patients with type 2 diabetes mellitus. Forty-two consecutive patients with type 2 diabetes (mean+/-SD 54+/-10 years, 22 women and 20 men) were studied. Baroreflex sensitivity negatively correlated with the maximum and minimum QTc intervals as well as QT/QTc dispersion. However, the high-frequency power and the ratio of low-frequency power to high-frequency power of heart rate variability did not correlate with any QT indices. The percent washout rate of (123)I-metaiodobenzylguanidine positively correlated with QT/QTc dispersion, but not with maximum and minimum QTc intervals. Our findings suggest that cardiac vagal dysfunction is related to QT interval prolongation while both sympathetic and vagal dysfunctions are related to increased QT dispersion in type 2 diabetic patients. Baroreflex sensitivity and percent washout rate of (123)I-metaiodobenzylguanidine may be useful parameters indicating the abnormalities of the cardiac ventricular repolarization in this population.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Sistema Nervoso Autônomo
/
Diabetes Mellitus Tipo 2
/
Coração
Tipo de estudo:
Prognostic_studies
Limite:
Adult
/
Aged
/
Female
/
Humans
/
Male
/
Middle aged
Idioma:
En
Revista:
Int J Cardiol
Ano de publicação:
2004
Tipo de documento:
Article