Evaluation of the use of electrocardiogram monitoring in patients on psychotropic medications that have a risk of QT prolongation

Abstract

Introduction:Many psychotropic medications carry a risk of prolonging the QT interval and increasing the risk of developing Torsade de pointes (TdP). The goal of this study was to evaluate whether patients taking psychotropic agents with a known risk of TdP are being monitored at a community hospital through the use of electrocardiograms (EKGs).Methods:This was a retrospective chart review of 100 adult patients—50 from general medicine floors and 50 from psychiatric units—who were taking at least one psychotropic agent with a known risk of TdP during hospitalization.Results:The mean number of medications with QT-prolongation risk administered to the psychiatric and general medicine patients was 4.2 ± 1.7 and 3.9 ± 2.0, respectively (P = .7484). Thirty-two of the psychiatric patients (64%) and 48 of the general medicine patients (96%) received EKGs during their hospitalization (P < 0.0001). Of those newly starting the target medications, 58% (18 of 31) of the psychiatric patients and 71% (5 of 7) of the general medicine patients received a baseline EKG. The difference was not statistically significant (P = .6807). Overall, 8 patients (8%) had corrected QT (QTc) intervals >500 ms. Four had repeat EKGs performed, and none had medication changes made to decrease TdP risk.Discussion:Many inpatients on psychiatric medications received multiple medications with a risk of TdP, but not all received monitoring through baseline or repeat EKGs when warranted. Patients with QTc intervals >500 ms were not appropriately managed to lower their risk of TdP. Pharmacists thus can help improve the monitoring and management of QT prolongation.

A literature-based algorithm for the assessment, management, and monitoring of drug-induced QTc prolongation in the psychiatric population

“…Common findings in the literature review which guided the development of this algorithm include the use of CredibleMeds ® as an important evidence-based resource, as well as the importance of cardiac risk stratification in the assessment and management of drug-induced QTc prolongation. Studies have shown that prescribers do not routinely screen for cardiac risk factors in psychiatric patients 53,56,57…”

“…In addition, because ECG monitoring may not be possible or readily accessible in both outpatient and inpatient settings, or in all psychiatric facilities, the algorithm developed highlights the importance of assessing the associated risk factors as early as possible before making recommendations on the use of medications with QTc-prolonging risk, primarily those listed as Category 1–3 by CredibleMeds ® or those that are known inhibitors of the hERG IKr channel 11,49,53,56–58. Current research initiatives, such as the Comprehensive in vitro Proarrhythmia Assay (CiPA), are developing and validating a model to test the proarrhythmic risk of drugs by assessing the effect of drugs on multiple ion channels and integrating ECG analysis in early phase I clinical trials to better predict proarrhythmic risk 59.…”