Effect of Chronic Arsenic Exposure from Drinking Waters on the QT Interval and Transmural Dispersion of Repolarization

Abstract

This study investigated the effects of chronic arsenic exposure on QT- and QTc-interval prolongation, QTc dispersion (QTcd) and transmural dispersion of repolarization (TDR). We compared cardiac parameters from 40 male subjects chronically exposed to arsenic (group A) with those of 40 male subjects not exposed to arsenic (group B). Although subjects in both groups had non-corrected QT intervals within normal limits, subjects in group A had significantly longer QTc and QTcd intervals compared with group B. A total of 70% of group A compared with 10% of group B had QTcd values > 50 ms. The mean TDR value was also significantly higher in group A compared with group B. Although non-corrected QT intervals were within normal limits, those subjects chronically exposed to arsenic had a slight QT prolongation and a higher prevalence of subtle repolarization abnormalities, which might be clinically relevant.

Arsenic-Induced QT Dispersion is Associated with Atherosclerotic Diseases and Predicts Long-Term Cardiovascular Mortality in Subjects with Previous Exposure to Arsenic: A 17-Year Follow-Up Study

“…Indeed, subjects in the status of current and chronic arsenic exposure could be involved with ion channelopathies and coronary atherosclerosis-related ischemia all together [7]. A recent study found that the measure of QTc dispersion and transmural dispersion of repolarization were significantly higher in chronically arsenic-exposed subjects compared with nonexposed subjects [42].…”

Mechanisms of action for arsenic in cardiovascular toxicity and implications for risk assessment

“…Numerous studies have assessed subclinical and intermediate cardiovascular endpoints that are surrogate endpoints commonly utilized in cardiovascular research, such as blood pressure/ hypertension (e.g., Guha Mazumder et al, 2012;Islam et al, 2012;Kim and Lee 2011;Jones et al, 2011;Chen et al, 2007;Kwok et al, 2007), QT prolongation (the QT interval on a surface electrocardiogram represents the depolarization and subsequent repolarization of the heart's ventricles, and as the interval lengthens, an individual is at greater risk for ventricular tachyarrhythmias) and other arrhythmic changes (e.g., Wang et al, 2009;Mordukhovich et al, 2009;Yildiz et al, 2008;Chen et al, 2007a), and intima media thickness (iMT) (e.g., Wang et al, 2009;Chen et al, 2006Chen et al, , 2013cOsorio-Yáñez et al, 2013). For each of the aforementioned changes, results are inconsistent, even at moderate to high exposure levels.…”

The health effects of exposure to arsenic-contaminated drinking water: a review by global geographical distribution

“…Chronic diseases have also been correlated with low-to-moderate arsenic exposure in Europe (Yildiz et al 2008;Medrano et al 2010;Dragana et al 2013). An ecological study in Spain reported that raised mortality rates for cardiovascular disease were associated with arsenic exposure at 10-118 μg/L (Medrano et al 2010).…”

“…Epidemiological evidence concerning the positive association between arsenic exposure and various health endpoints gradually increased in Europe (Börzsönyi et al 1992;Yildiz et al 2008;Medrano et al 2010;Leonardi et al 2012;Dragana et al 2013). Basal cell carcinoma of the skin was confirmed to be positively associated with exposure to arsenic through drinking water with concentrations < 100 μg/L by the Arsenic International Journal of Environmental Health Research 11…”