Optimal Settings for Anti Tachycardia Pacing (ATP) on ICD

This is a pragmatic, two-group, cluster randomized trial designed to compare strategies for the Anti Tachycardia Pacing (ATP)-setting in the ventricular tachyarrhythmias (VT) zone when implanting a new implantable cardioverter defibrillator (ICD) in patients with heart disease in hospitals in Denmark. The strategies are: "Burst" or "Ramp" after 1. ATP (which is always burst) in VT zone. VT zone is defined between 180-249 (up to 269 in special cases) heartbeats per minute. The ICD will give either: Burst: The ICD is programmed to give ATP with 4 bursts. Or Ramp: The ICD is programmed to give ATP with 1 burst and 3 ramps. The participating hospitals will be assigned to one of two intervention strategies for periods of 4-months. The given intervention will follow the patient/ICD throughout the life time of the ICD, but with the possibility to reprogram at any time (intention to treat). It is calculated that the study needs a total of 398 events (second to fourth ATP), which is estimated to require 3980 implanted ICDs. The participants will be followed until the end of the ICD life, which is estimated to be around 10 years.

NCT Number	NCT07354347
Lead Sponsor	Rigshospitalet, Denmark Collaborators: The Novo Nordic Foundation
Conditions	Heart Disease, Implantable Cardioverter Defibrillator (ICD), Heart Rhythm Disorders, Ventricular Tachyarrhythmias
Enrollment	3,980 participants
Start Date	2026-02-01
Primary Completion	2041-07-31 (estimated)
Study Completion	2041-07-31 (estimated)
Updated on ClinicalTrials.gov	2026-01-27