Study Evaluating Dexmedetomidine in the Acute Treatment of Electrical Storm (SEDATE)

The objective of this study is to determine if there is a meaningful benefit to using the sedative medication dexmedetomidine in the acute treatment of patients with recurrent ventricular arrhythmias, known as electrical storm. This will be a multi-centre, double-blinded, placebo-controlled, randomized trial. Patients with electrical storm will be randomized to receive 48 to 72 hours of dexmedetomidine or placebo as part of their initial treatment in an intensive care unit.

Study Overview

• Status: Recruiting
• Conditions: Ventricular Fibrillation; Ventricular Tachycardia; Ventricular Arrhythmias; Recurrent Ventricular Tachycardia
• Intervention / Treatment: Drug: Dexmedetomidine; Drug: Normal saline

Detailed Description

Electrical storm (ES), defined as three or more sustained or treated ventricular arrhythmias in a 24-hour period, is a life-threatening condition that is associated with significant short- and long-term mortality. Autonomic dysfunction from increased sympathetic tone and the catecholamine surge from defibrillator shocks can precipitate recurrent ventricular arrhythmias and exacerbate ES. Although the mainstay of treatment are anti-arrhythmic drugs, sedative agents and procedures are commonly used to decrease sympathetic tone. These therapies have been studied in refractory ES but the benefit of early sedation remains unclear.

Alpha-2 agonism with dexmedetomidine can provide conscious sedation without the need for mechanical ventilation. Dexmedetomidine has been found to reduce ventricular arrhythmia events in non-ES patients in the intensive care unit and in the peri-operative period. Its antiarrhythmic properties are thought to be due to catecholamine suppression, prolonging electrical refractory periods, and increasing vagal tone. Its rapid onset and favorable safety profile render alpha-2 agonism with dexmedetomidine a potentially valuable therapy for patients with ES.

This study is a multi-centre, double-blinded, placebo-controlled, randomized trial that will evaluate the effectiveness of dexmedetomidine in the acute treatment of ES. Consecutive patients admitted to an intensive care unit will be randomized to receive dexmedetomidine or placebo at the time of presentation. The study drug will be titrated to a maintenance dose and continued for 48 hours before being weaned.

• Study Type: Interventional
• Enrollment (Estimated): 192
• Phase: Phase 3

Contacts and Locations

• Study Contact: Name: Benjamin Hibbert, MD PhD; Email: hibbert.benjamin@mayo.edu
• Study Contact Backup: Name: F. Daniel Ramirez, MD MSc; Phone Number: 613-696-7402; Email: dramirez@ottawaheart.ca

Study Locations

• Canada
  • Ontario
    • Ottawa, Ontario, Canada, K1Y 4W7
      • Recruiting
      • University of Ottawa Heart Institute
      • Contact: F Daniel Ramirez, MD; Phone Number: 613-696-7402; Email: dramirez@ottawaheart.ca

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

- All patients admitted to an intensive care unit with electrical storm over the age of 18 years will be approached for enrollment.

Exclusion Criteria:

• Refractory shock lasting for more than 30 minutes unrelated to ventricular arrhythmias (VAs), defined as requiring two or more vasopressors
• SCAI class D or E cardiogenic shock
• Cardiac arrest(s) with a no-flow and low-flow total time of greater than 10 minutes prior to recruitment.
• ST-segment elevation myocardial infarction (STEMI)-induced VA with signs of active ischemia.
• Bradycardia with heart rate less than 40 beats per minute, bradycardia-induced ventricular tachyarrhythmia, second degree Mobitz type 2 or greater atrioventricular block in the absence of a pacemaker.
• Pregnancy
• Known dexmedetomidine allergy or intolerance
• Inability to obtain consent from patient or substitute decision maker.
• Patients who have received dexmedetomidine or clonidine during the 24 hours prior to randomization

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Dexmedetomidine; Participants randomized to receive dexmedetomidine will be started at a dose of 0.3 mcg/kg/hr and titrated to a target dose of 1.0 mcg/kg/hr. Once the participant reaches their maximum tolerated dose (as decided by the blinded treating physician), they will continue treatment for 48 ± 6 hours. This will be followed by a weaning phase that will similarly be at the discretion of the treating physician.	Drug: Dexmedetomidine; Dose range: 0.3 mcg/kg/hr to 1 mcg/kg/hr.; Other Names: Precedex
Placebo Comparator: Placebo; Participants randomized to receive placebo will be started on normal saline. In similar fashion to the active comparator, participants will be titrated to their maximal tolerated dose, continue treatment for 48 ± 6 hours, and be weaned at the discretion of the blinded treating physician.	Drug: Normal saline; Programed as dexmedetomidine on infusion pump.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The primary outcome is a composite of the following: 1. All-cause in-hospital death AND/OR 2. Any in-hospital ventricular arrhythmia requiring treatment after study drug initiation.	Defined as anytime after the participant starts receiving dexmedetomidine or normal saline placebo	Duration of index hospitalization - an average of 2 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
All-cause in-hospital death	Defined as anytime after the participant starts receiving dexmedetomidine or normal saline placebo	Duration of index hospitalization - an average of 2 weeks
Ventricular arrhythmia requiring treatment after study drug initiation	Defined as anytime after the participant starts receiving dexmedetomidine or normal saline placebo	Duration of index hospitalization - an average of 2 weeks
Resuscitated cardiac arrest after study drug initiation	Defined as anytime after the participant starts receiving dexmedetomidine or normal saline placebo	Duration of index hospitalization - an average of 2 weeks
Renal failure requiring new initiation of renal replacement therapy after study drug initiation	Defined as anytime after the participant starts receiving dexmedetomidine or normal saline placebo	Duration of index hospitalization - an average of 2 weeks
Intubation following study drug initiation	Defined as anytime after the participant starts receiving dexmedetomidine or normal saline placebo	Duration of index hospitalization - an average of 2 weeks
Length of stay in the intensive care unit	Defined as anytime after the participant starts receiving dexmedetomidine or normal saline placebo	Duration of index hospitalization - an average of 2 weeks
Length of stay in hospital	Defined as anytime after the participant starts receiving dexmedetomidine or normal saline placebo	Duration of index hospitalization - an average of 2 weeks
Need for mechanical circulatory support device after study drug initiation	Defined as anytime after the participant starts receiving dexmedetomidine or normal saline placebo	Duration of index hospitalization - an average of 2 weeks
Ventricular Arrhythmia requiring treatment only during active study drug treatment	Defined as anytime the participant is receiving dexmedetomidine or normal saline placebo	Duration of index hospitalization - an average of 2 weeks
Pacing or treatment with isoproterenol for treatment of bradyarrhythmia after study drug initiation.	Defined as anytime after the participant starts receiving dexmedetomidine or normal saline placebo	Duration of index hospitalization - an average of 2 weeks

Collaborators and Investigators

• Sponsor: Ottawa Heart Institute Research Corporation

Study record dates

Study Major Dates

• Study Start (Actual): May 8, 2024
• Primary Completion (Estimated): May 8, 2027
• Study Completion (Estimated): August 1, 2027

Study Registration Dates

• First Submitted: February 9, 2024
• First Submitted That Met QC Criteria: February 20, 2024
• First Posted (Actual): February 28, 2024

Study Record Updates

• Last Update Posted (Actual): December 17, 2025
• Last Update Submitted That Met QC Criteria: December 16, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: Sedation; Dexmedetomidine; Precedex; Electrical Storm; Ventricular Electrical Storm; Recurrent Ventricular Arrhythmias; Recurrent Ventricular Tachycardia
• Additional Relevant MeSH Terms: Cardiac Conduction System Disease; Cardiovascular Diseases; Pathologic Processes; Heart Diseases; Arrhythmias, Cardiac; Tachycardia; Pathological Conditions, Signs and Symptoms; Tachycardia, Ventricular; Ventricular Fibrillation; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Pharmaceutical Preparations; Azoles; Imidazoles; Crystalloid Solutions; Isotonic Solutions; Solutions; Dexmedetomidine; Saline Solution
• Other Study ID Numbers: ES613

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The study data, protocol, SAP, ICF, and CSR will be made available at study completion/publication.
• IPD Sharing Time Frame: Study completion
• IPD Sharing Access Criteria: The above will be made publicly available
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No