Community pharmacist use of mobile ECG to inform drug therapy decision making for patients receiving QTc prolonging medications

Abstract

Introduction: For patients using QTc prolonging medications, the health care system is challenged to mitigate the risk of drug-induced long-QT syndrome (DiLQTS) and sudden cardiac death (SCD). Community pharmacists (CPs) receive QTc alerts when dispensing but intervene infrequently. Personal electrocardiogram (ECG) monitors are a new, inexpensive technology that could provide additional patient risk information to identify individuals with a prolonged QTc interval in real time. Objectives: (1) Describe QTc interval-prolonging medications, QTc interval calculations, and associated interventions and prescriber responses for a CP-delivered QTc interval assessment program, and (2) Describe patient satisfaction with the service. Methods: A prospective study of 9-month duration in three community pharmacies in Iowa. CPs were trained to measure QTc interval using the KardiaMobile ECG monitor. English-speaking patients aged ≥18 years were recruited to have a 30 seconds ECG tracing if the CP received a computer QTc-related alert or had concern about QTc effect/interaction. CPs used professional judgment regarding prescriber contact but were required to contact the prescriber if the QTc interval was prolonged (>470 ms males, >480 ms females). Results: There were 53 patients who met study criteria and participated in the service. Mean age was 55.1 years, 38 (72%) were female, and 19 (36%) received newly prescribed QTc interval-prolonging medications. A computer-generated QTc alert was present for 36 (68%) of participants. CPs contacted a prescriber for 6 (11%) patients regarding concern for DiLQTS (mean QTc 495 ms). Of these six instances, three had QTc prolongation requiring mandatory prescriber contact (mean QTc 529 ms). Prescriber contact resulted in medication changes for 3 (50%) patients. Conclusion: CPs were able to measure QTc interval, identify patients at risk for DiLQTS, and make accepted medication therapy recommendations related to QTc prolongation. CP assessment of QTc interval may be a useful approach to improve risk stratification of individuals at risk of DiLQTS and SCD. Trial registration: Clinical Trials.gov Identifier: NCT04000542.