Prolongation of the QT interval in palliative care patients

Abstract

Prolonged QT interval on the electrocardiogram (ECG) is associated with an increased risk of cardiac arrhythmia and sudden death. Many drugs used in palliative medicine increase the QT interval and several have had their licenses withdrawn or severely restricted. The relative importance of prolonged QT interval will increase for palliative medicine physicians when dealing with patients with longer prognoses and especially cardiac disease. Given these safety concerns, the aim of this study was to determine the prevalence of a prolonged QT interval in palliative care patients who were not in the terminal stage and were referred to a specialist service. Of 300 patients, 47 (16%) had prolonged QTc but only two had QT >500ms. The presence of coexistent cardiac disease or high levels of serum alkaline phosphatase appear to be the clinical features most robustly associated with a prolonged QTc. Although prolonged QTc is relatively common in patients referred to a specialist palliative care service, severely prolonged QT is rare.