Short QT Interval Prevalence and Clinical Outcomes in a Pediatric Population

Abstract

Background-Risk associated with short QT interval has recently received recognition. European studies suggest a prevalence of 0.02% to 0.1% in the adult population, but similar studies in pediatric patients are limited. We sought to determine the prevalence of short QT interval in a pediatric population and associated clinical characteristics and outcomes. Methods and Results-Retrospective review of an ECG database at a single pediatric institution. The database was queried for ECGs on patients ≤21 years with electronically measured QTc of 140 to 340 ms. Patients with QTc of 140 to 340 ms confirmed by a pediatric electrophysiologist were identified for chart review for associated clinical characteristics, symptoms, and outcome. Patients with and without symptoms were compared in an attempt to identify variables associated with outcome. The query included 272 504 ECGs on 99 380 unique patients. Forty-five patients (35 men, 76%) had QTc ≤340 ms, for a prevalence of 0.05%. Median age was 15 years (interquartile range, 2-17), median QT 330 ms (interquartile range, 280-360), and median QTc 323 ms (IQR,(313)(314)(315)(316)(317)(318)(319)(320)(321)(322)(323)(324)(325)(326)(327)(328)(329)(330)(331)(332). Women had significantly shorter QTc compared with men (312 versus 323 ms; P=0.03). Two deaths were noted in chart review-one from respiratory failure and the second of unknown pathogenesis in a patient with dilated cardiomyopathy. Conclusions-Short QT interval was a rare finding in this pediatric population, with a prevalence of 0.05%. Male predominance was identified, although the median QT interval was significantly shorter in women. There seem to be no unifying clinical characteristics for this pediatric patient cohort with short QT interval. (Circ Arrhythm Electrophysiol.

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Modeling Short QT Syndrome Using Human‐Induced Pluripotent Stem Cell–Derived Cardiomyocytes

“…Short QT syndrome (SQTS) is a rare, inheritable cardiac electrical disease characterized by a shortened corrected QT interval (QTc) and associated with a risk of SCD. The prevalence of SQTS is 0.02% to 0.1% with a male predominance . The majority of cardiac events (>80%) in SQTS patients occur under resting conditions or during sleep.…”

Drug Testing in Human‐Induced Pluripotent Stem Cell–Derived Cardiomyocytes From a Patient With Short QT Syndrome Type 1

“…The clinical presence of SQTS may be expanded from asymptomatic cases, palpitations, syncope, and dizziness to atrial fibrillation or SCD . The prevalence of SQTS is low, around 0.02–0.1% in the adult population and 0.05% in the pediatric population, with a male predominance . The diagnostic and treatment approaches are challenging for physicians due to the low prevalence and rarity of cases.…”

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