Does Infection Prolong the QT Interval

BACKGROUND: The corrected QT interval (QTc) is a strong predictor of ischemic heart disease and cardiovascular mortality. It may trigger lethal arrhythmias and sudden death. Risk factors include electrolyte disorders, medications, prior cardiovascular disease and genetic predisposition. We previously demonstrated that QTc intervals are prolonged in patients hospitalized with pneumonia, regardless which antibiotics were given. It is unclear whether QTc prolongation is associated with pneumonia itself or whether it occurs with other infections. Our purpose was to investigate any association between hospitalization for infection and QTc prolongation. METHODS: We enrolled 169 patients, 160 of whom were used for analysis. QTc was measured in seconds by routine electrocardiogram (ECG) upon admission. Subsequently, daily ECGs were performed for three days, or until discharge (whichever occurred sooner). When clinically significant QTc prolongation was detected, possible causes were investigated. RESULTS: Clinically significant prolongation was not observed in any patient. The QTc was slightly longer in patients hospitalized for pneumonia or upper respiratory tract infections on admission. It was also prolonged in men, in patients with ischemic heart disease, hypertension, history of cerebrovascular accident or cancer. A very slight trend for prolongation was observed between the first and second day of monitoring, however it later returned to baseline levels. Nearly 54% of study participants had positive systemic inflammatory response syndrome scores, however no association was detected between their score and baseline QTc, or any subsequent prolongation. CONCLUSIONS: We found no association between hospitalization due to infection and prolongation of the QTc interval. This article is protected by copyright. All rights reserved.