Acute effects of synthetic cannabinoids on ventricular repolarization parameters

Objective: An association between ventricular repolarization parameters (VRPs) and ventricular arrhythmias has been demonstrated in previous studies. However, there are limited data related to a relationship between synthetic cannabinoids (SCs) and VRPs. The aim of this study was to analyze the acute effects of SCs on VRPs using electrocardiogram (ECG) measurements of the T-peak to T-end interval (Tp-e), Tp-e/QT ratio, and Tp-e/corrected QT (QTc) ratio.
Methods: The present study included 58 patients who were admitted to the emergency department who used SCs (SC +) between 2014 and 2016, and 50 healthy control subjects (SC -). The QT and QTc intervals, Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios were measured from a 12-lead ECG. These parameters were compared between groups and correlation analysis was performed.
Results: The Tp-e and QTc intervals were significantly higher in SC + patients when compared with the SC- group (92.2±10.0, 77.4 ±9.3, p<0.001; 434.5±30.8, 410.9±27.3, p<0.001, respectively). Tp-e/QT and Tp-e/QTc ratios were greater in SC + patients in comparison with SC – participants (0.26±0.02, 0.22±0.02, p<0.001; 0.21±0.02, 0.18±0.02, p<0.001, respectively). Significant correlations were found between the use of SCs and the Tp-e interval (r=0.610; p<0.001), Tp-e/QT (r=0.655; p<0.001) and Tp-e/ QTc ratios (r=0.437; p<0.001).
Conclusion: The Tp-e interval, Tp-e/QT and Tp-e/QTc ratios were greater in subjects who used SCs. Therefore, SC users might have an increased risk of ventricular arrhythmia.

Keywords: Acute effects, synthetic cannabinoids; ventricular repolarization parameters.