Drug-Induced QT Prolongation, Torsades de Pointes, Ventricular Arrhythmias and Cardiac Arrest: A Systematic Review

Background: Drug-induced QT prolongation is a recognized adverse effect of numerous medications and is associated with an increased risk of torsades de pointes (TdP), ventricular arrhythmias, cardiac arrest, and mortality.However, the incidence and clinical consequences of drug-induced QT prolongation remain incompletely defined across different patient populations.Methods: A systematic review and meta-analysis was conducted according to PRISMA 2020 guidelines.PubMed, Embase, Scopus, and Web of Science were searched from database inception through May 2026.Observational studies, cohort studies, registrybased investigations, and case-control studies evaluating drug-induced QT prolongation and related adverse outcomes were included.The primary outcome was TdP, while secondary outcomes included ventricular arrhythmias, cardiac arrest, and mortality.Random-effects models were used to calculate pooled incidence estimates, and heterogeneity was assessed using the I² statistic.Results: Fourteen studies involving more than 4.9 million participants were included.The pooled incidence of drug-induced QT prolongation was 17% (95% CI: 11%-27%; I² = 96.8%).The pooled incidence of TdP was 4% (95% CI: 0%-30%; I² = 99.8%),while ventricular arrhythmias occurred in 2% of patients (95% CI: 0%-30%; I² = 95.2%).Major risk factors included female sex, advanced age, electrolyte abnormalities, cardiovascular disease, renal dysfunction, and concomitant use of multiple QT-prolonging medications.Conclusion: Drug-induced QT prolongation appears to be common and is associated with clinically significant arrhythmic complications.Careful ECG monitoring, optimization of modifiable risk factors, and judicious use of QT-prolonging medications are essential to improve patient safety and reduce adverse cardiovascular outcomes.