Development and early evaluation of clinical decision support for long QT syndrome population screening

Aim: Long QT syndrome (LQTS) is an inherited condition that predisposes individuals to prolongation of the QT interval and increased risk for Torsade de Pointes. Pathogenic variants in three genes - KCNH2, KCNQ1 and SCN5A - are responsible for most cases of LQTS, and recent advances in genetic testing have improved knowledge of the disease, increased access to follow-up, and reduced adverse cardiovascular outcomes. Methods: Based around our preemptive genetic screening platform which includes the three long QT genes listed above, we developed and implemented a clinical decision support (CDS) module that alerts prescribers whenever a QT-prolonging medication is ordered for patients with a genetic predisposition to LQTS. Results: Of the 13,777 individuals screened, twenty-seven tested positive for a pathogenic or likely pathogenic variant of KCNH2, KCNQ1 or SCN5A. In a subsequent early evaluation of the CDS and clinical processes, the number of QT-prolonging medications in this cohort decreased by 20% and new QT-prolonging medications were avoided in approximately 1/3 of new prescription orders. Conclusions: While long-term evaluation is needed, early data support the benefit of utilizing CDS in expanded roles, such as drug-gene-disease interactions where rare genetic variants intersect with everyday prescribing.