A study on QT interval in patients affected with inflammatory bowel disease without cardiac involvement.

Cardiac involvement has been studied quite extensively in patients affected by inflammatory bowel disease but, as of now, there is no data regarding QT alterations which are well known to be linked to the risk of dangerous arrhythmias. In this study, QT parameters were digitally measured on standard 12-lead ECG in a population of 20 patients affected by inflammatory bowel disease (IBD), with no prior (recent or old) history of cardiac disease and no evidence of electrolyte imbalance. Eighteen healthy subjects formed the control group. The results obtained using non-parametric statistics (Wilcoxon-Mann-Whitney test) showed that heart rate corrected QT interval (QTc) and QTc dispersion (QTc d) values were both significantly higher in IBD patients than in the control group. QTc rank sum values in patients affected by inflammatory bowel disease were 469 versus 311 in healthy subjects (Z = 1.939, p = 0.0263). QTc d rank sum values were 460 in IBD patients versus 320 in controls (Z = 1.686 with p = 0.0459). Regardless of the cause of these QT alterations, it appears evident that accurate monitoring of QT parameters is required in these patients who often experience electrolyte disturbances and who may, in some cases, be undergoing treatment with potentially cardiotoxic drugs such as infliximab.