Category: Federal Forum Posters
Purpose: QTc prolongation is an adverse effect of many medications that can lead to life-threatening arrhythmias, including TdP. When patients taking these drugs possess additional risk factors, chance of QTc prolongation increases exponentially. A recently published risk assessment tool categorizes patients age 65 and older taking both a potassium-lowering diuretic and a QTc-prolonging medication as high-risk. Despite vague recommendations from relatively outdated guidelines, newer literature recommends ECG monitoring whenever QTc-prolonging medications are initiated, regardless of baseline cardiac risk factors. This study’s objective is to determine rate of ECG monitoring in high-risk patients before initiating QTc-prolonging medications with known risk of TdP.
Methods: This retrospective chart review has been submitted to the Institutional Review Board for approval. Once granted, investigators will use structured query language within the electronic health records to identify patients age 65 or older taking a thiazide or loop diuretic, in addition to either ziprasidone, haloperidol, citalopram, escitalopram, or methadone over a three-year period. These agents were selected based off “high-risk” designation by Crediblemeds.org, defined as “drugs known to prolong the QTc interval and clearly associated with a known risk of TdP, even when taken as recommended”. Charts will be screened to reach a target enrollment of 100, with up to 30 patients representing each medication group. The primary endpoint is the rate of ECG monitoring at baseline, defined as 30 days before or up to 7 days after initiation of medication with known risk of TdP. The secondary endpoint will look for ECG monitoring at any time while prescribed one of these medications. Additional data will be analyzed to identify baseline characteristics and additional risk factors, including: age, gender, history of cardiovascular events, cardiovascular disease, diabetes mellitus, thyroid disorders, hypertension, and concomitant QTc-prolonging medications. Exclusion criteria include: patients younger than 65 years old, or patients taking any potassium-sparing diuretic.
Results: not applicable
Conclusion: not applicable
Danielle Waldron– PGY1 Resident, Veterans Health Care System of the Ozarks, Fayetteville, AR