Extract

Dear Sir

We appreciate the review by Berling et al., which was a useful reminder of the potential risks of torsades de pointes (TdP) in patients who are taking QT-prolonging medications.1

The finding that only 19% of the inpatients had an electrocardio graph (ECG) completed was surprisingly low. They too suggested this was low and presented literature supporting the potential benefit of using ECGs as a ‘low-cost screening tool’. Considering that many psychiatric medications are associated with QT-prolongation and other car diac risks, and that polypharmacy is not uncommon, we agree that ECGs should be completed regularly in inpatient units.

Berling and colleagues provide a table of all medications that patients in the study were prescribed, which is split into a short list ‘QT-prolonging agent with known risk of TdP’ (ami sulpride, citalopram, escitalopram, haloperidol, and methadone) and a long list ‘Other agents’. Among the ‘Other agents’ list we noted medications which cause QT-prolongation and some which have been else where classified as being a known risk of TdP, such as chlorpromazine (CPZ).2,3 They used the CredibleMeds website as a reference, which focusses on ‘quality of evidence and strength of associations’, but considering the significant risk associated with TdP we think it is prudent to remind readers of the risk of some of the ‘Other agents’, especially in high-risk patients and when concomitantly prescribing multiple medications that cause QT prolongation.