IntroductionSpecialized laboratory evaluation of supraventricular tachycardia in children may occur, but the utility is unknown. The study objectives are to assess the type, frequency, and results of specialized laboratory testing performed in pediatric patients presenting with new-onset supraventricular tachycardia. We hypothesized that when specialized laboratory testing occurs (particularly for cardiac failure, toxicologic, inflammatory, and thyroid diseases), the results are generally within normal limits. MethodsThis is a retrospective descriptive study using an electronic health record database (TriNetX, Inc). We collected and evaluated the following data of subjects aged younger than 18 years with a first-time supraventricular tachycardia diagnosis: demographics, diagnostic codes, deaths, and laboratory codes/results (natriuretic peptide B, natriuretic peptide B prohormone N-terminal, troponin I, toxicology testing, inflammatory markers, and thyroid studies). ResultsA total of 621 subjects (524 [84.4%] without laboratory testing, 97 [15.6%] with laboratory testing) were included. Thyroid studies (65 [10.5%]) were the most frequent laboratory study performed followed by cardiovascular specific studies (35 [5.6%]), inflammatory markers (21 [3.4%]), and toxicology tests (10 [1.6%]) (P = .002). Obtained laboratory testing was more frequent with older subjects, females, and need for emergency, hospital, and critical care services. DiscussionCardiac-specific and noncardiac laboratory testing is frequently ordered for pediatric patients who present with supraventricular tachycardia. Thyroid studies were the most common laboratory testing ordered, but abnormal results only occurred in less than a quarter of subjects. These findings may highlight a quality improvement opportunity for emergency nurses and practitioners in the practice of obtaining laboratory tests to better reflect high-value evidence-based care for this vulnerable population.