Delayed QT Prolongation: Derivation of a Novel Risk Factor for Adverse Cardiovascular Events from Acute Drug Overdose

INTRODUCTION: In ED patients with acute drug overdose involving prescription medication and/or substances of abuse, severe QTc prolongation (> 500 ms) is predictive of adverse cardiovascular events (ACVE), defined as myocardial injury, ventricular dysrhythmia, shock, or cardiac arrest. However, it is unclear whether delayed severe QTc prolongation (dsQTp) is a risk factor for ACVE and if specific clinical factors are associated with occurrence of dsQTp. METHODS: A secondary analysis of a prospective cohort of consecutive adult ED patients with acute drug overdose was performed on patients with initial QTc 45 years and polydrug (≥ 3) overdoses. CONCLUSION: In this large secondary analysis of ED patients with acute drug overdose, dsQTp was an independent risk factor for in-hospital occurrence of ACVE. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13181-021-00855-2.