Prolongamento do intervalo QT associado à magnésio baixo em alcoolistas crônicos

• Autor(a) principal: Moulin, Stephanie Rezende Alvarenga
• Data de Publicação: 2014
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/5289
• topic: Alcoholism; Cardiac arrhythmias; Electrocardiogram; Magnesium; Long QT syndrome; Síndrome do QT longo; Arritmia cardíaca; Eletrocardiograma; Medicina; Arritmia - Coração, doenças; Alcoolismo; Magnesio; 61

BACKGROUND: Alcoholism is a high prevalence addiction worldwide. Abusive alcohol intake is associated with cardiac arrhythmias. Chronically, it seems that alcohol is associated with cardiac electrical disorders such as prolongation of the QT interval, an unusual change between healthy subjects (0.0017 to 0.31%), which may lead to tachyarrhythmias and sudden death. QT prolongation can be associated to alcohol intake and hypomagnesaemia. METHODS and RESULTS: We compared the electrocardiographic changes and plasma magnesium in active alcoholics (n=62), more than 7 days abstinent alcoholics (n=104) and non-alcoholics (n=45) attending to a outpatient clinic. There was a higher prevalence of long QT in active alcoholics than in abstinent alcoholics (16% vs. 2% OR=9.81 p=0.011), and no abnormalities in non-alcoholics. Heart rate was higher among active alcoholics, as well as the greater the presence of tachycardia in this group. The other ECG parameters were similar frequencies between the groups. Hypomagnesaemia was also more frequent in active alcoholics (26%) than in abstinent alcoholics (10% OR=3.11 p=0.013) and non-alcoholics (5% OR=6.30 p=0.022). Serum magnesium levels showed an inverse relationship (r=0.39; p<0.005) to duration of the corrected QT interval in active alcoholics (Beta = -35.1 ± 11.6 ms/(mg/dL) but not in the other two groups. Potassium and Calcium dosages were similar between groups. The presence of hypocalcemia was significantly more common among those with long QT, but when done the analysis of correlation between calcium and QT interval for active alcoholics, there was no statistical significance (p = 0.238). CONCLUSION: There was a higher association of long QT and hypomagnesaemia in active chronic alcoholics. Low magnesium was predictor of QT interval prolongation. The dosage of ions and performing electrocardiogram are important tests for early diagnosis of changes that can trigger life-threatening arrhythmias in chronic alcoholics and should be routinely required in the care of Alcohol Withdrawal Syndrome.