The Current Landscape of Ventricular Tachycardia Trials: A Systematic Review of Registered Studies

Background Although there are evolving techniques and technologies for treating ventricular tachycardia (VT), the current landscape of clinical trials for managing VT remains understudied. Objective The objective of this study was to provide a systematic characterisation of the interventional management of VT through an analysis of the ClinicalTrials.gov, clinicaltrialsregister.eu, anzctr.org.au and chictr.org.cn databases. Methods We queried all phase II to IV interventional trials registered up to November 2023 that enrolled patients with VT. Published, completed but unpublished, terminated, or ongoing trials were included for fi nal analysis. Results Of the 698 registered studies, 135 were related to VT, with 123 trials included in the fi nal analysis. Among these trials, 25 (20%) have been published, enrolling a median of 35 patients (interquartile range [IQR] 20-132) over a median of 43 months (IQR 19-62). Out of the published trials, 14 (56%) were randomised, and 12 (48%) focused on catheter ablation. Twenty-two (18%) have been completed but remain unpublished, even after a median of 36 months (IQR 15-60). Furthermore, 27 (22%) trials were terminated or withdrawn, with the most common cause being poor enrolment. Currently, 49 (40%) trials are ongoing and novel non-ablative technologies, such as radioablation and autonomic modulation, account for 35% and 8% of ongoing trials, respectively. Conclusions Our analysis revealed that many registered trials remain unpublished or incomplete, and randomised controlled trial evidence is limited to only a few studies. Furthermore, many ongoing trials are focused on non-catheter ablation-based strategies. Therefore, larger pragmatic trials are needed to create stronger evidence in the future.