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Ventricular repolarization in diabetic patients: characterization and clinical implications
David Clemente1, Telmo Pereira, Susana Ribeiro
1Unidade de Cuidados de Saúde Personalizados de Salvaterra de Magos, Portugal. david_s_clemente@hotmail.com
Arquivos Brasileiros De Cardiologia
|October 31, 2012
Summary
Diabetes significantly increases ventricular repolarization abnormalities, raising the risk of malignant arrhythmias. This study highlights prolonged QT intervals and increased dispersion in diabetic patients, contributing to electrical instability.
Area of Science:
- Cardiology
- Diabetology
- Electrophysiology
Background:
- Diabetes mellitus is a prevalent chronic condition with increasing incidence.
- Diabetic patients face elevated cardiovascular mortality, with malignant ventricular arrhythmias as a suspected factor.
Purpose of the Study:
- To investigate the impact of diabetes on ventricular repolarization parameters.
- To assess how these changes increase susceptibility to malignant ventricular arrhythmias and sudden cardiac death.
Main Methods:
- Compared 110 diabetic patients with 110 age, gender, and race-matched controls.
- Evaluated ventricular repolarization parameters including QT and QTc intervals, dispersions, and T-wave/j-T intervals using electrocardiograms (ECG).
- Corrected QT intervals using Bazett's formula.
Main Results:
- Diabetic patients exhibited significantly higher QTc(max), QTc(mean), QT dispersion, QTc dispersion, T(peak)-T(end) dispersion, and jT(peak)-jT(end) dispersion compared to controls (p < 0.001).
- Diabetic patients showed prolonged QTc intervals (5.5%) and increased dispersions in T(peak)-T(end) (16.4%) and jT(peak)-jT(end) (12.7%).
- No prolonged repolarization parameters were observed in the control group.
Conclusions:
- Diabetes leads to prolonged and spatially dispersed ventricular repolarization.
- These repolarization changes may enhance ventricular electrical instability.
- This instability is a potential contributor to malignant ventricular arrhythmias in diabetic individuals.
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