Cardiologist-Administered Midazolam vs. Anaesthesiologist-Assisted Propofol Sedation For Transoesophageal Echocardiography-Guided Cardioversion of Atrial Fibrillation

NCT07571447 | Not Yet Recruiting Phase 4

• 3 other identifiers: CARDIOZOLAM-11-10-72-10-261-16-02-95-26
• Study Type: interventional
• Target: 220
• Locations: 1 country
• Sites: 2

Brief Summary

Irregular heart rhythms, known as atrial fibrillation or atrial flutter, are common conditions that can increase the risk of stroke and heart failure. A standard treatment to restore a normal rhythm is a controlled electric shock, known as cardioversion. However, if the irregular rhythm has lasted more than 24 hours, if the duration is uncertain, and if the patient has not been on blood-thinning medication for at least three weeks, doctors must first check for blood clots in the heart. This is done using a special ultrasound scan of the heart through the food pipe. Both the scan and the electric shock treatment require sedation to make the patient relaxed or asleep. The scan uses mild sedation from a cardiologist, while the shock needs a stronger sedative given by an anaesthesiologist. But needing this extra doctor can cause delays, so patients often wait longer for treatment and to go home. This study will test whether a cardiologist can safely handle both steps using a sedative called midazolam. This study will include 220 adults at multiple hospitals in Denmark and compare this new approach to standard care. Researchers will track how quickly patients go home, how well the treatment works, any serious side effects, what patients think about the experience, and how much money can be saved. If proven safe and effective, this new method could reduce treatment delays, shorten hospital stays, and lower healthcare costs-ultimately improving care for patients and making the healthcare system more efficient.

Conditions

Atrial Fibrillation (AF); Atrial Flutter

Keywords

Direct current cardioversion; Transoesophageal echocardiography

Outcome Measures

Primary Outcomes (1)

• Time-to-discharge

  The primary outcome is time-to-discharge after TOE, with the corresponding endpoint operationalised as the mean number of minutes from randomisation (post-TOE) to formal hospital discharge. This outcome is designed to capture the impact on the healthcare system by serving as a proxy for resource use, where shorter time-to-discharge may reduce bed occupancy, staff workload, and overall hospital costs.

  Day 1.

Secondary Outcomes (4)

• Time-to-shock delivery

  From time of randomisation until the time of first shock delivery, assessed on day 1

• Conversion to sinus rhythm

  Periprocedural

• Complication rate

  From time of sedation initiation until discharge (within 8 hours post-DCC on average)

• Patient-reported outcomes

  Postprocedural, with the questionnaire being administered after DCC and before discharge (within 8 hours post-DCC on average)

Study Arms (2)

Cardiologist-only (intervention)

EXPERIMENTAL

Other: One-step cardiologist-only midazolam sedation

With anaesthesiology assistance (standard care)

ACTIVE COMPARATOR

Other: Two-step anaesthesiologist-assisted propofol sedation

Interventions

One-step cardiologist-only midazolam sedation OTHER

TOE-guided DCC performed under continuous cardiologist-administered midazolam sedation, without anaesthesiologist involvement. Midazolam is administered intravenously at the discretion of the treating cardiologist. Non-binding dosing guidance is provided to support clinical practice, but dosing may be individualised as clinically indicated. * For the TOE phase, suggested dosing includes an initial IV dose of 1.25-5.0 mg, with repeat doses of 1.25-2.5 mg as needed, and a suggested maximum cumulative dose of 20 mg. * For the DCC phase, suggested dosing includes an initial IV dose of 2.5-7.5 mg, with repeat doses of 2.5 mg as needed. A suggested maximum cumulative dose of 25 mg applies, including doses administered during the TOE phase.

Cardiologist-only (intervention)

Two-step anaesthesiologist-assisted propofol sedation OTHER

TOE performed under cardiologist-administered sedation followed by a wake-up period and subsequent DCC performed under propofol sedation administered by an anaesthesiologist. Sedation for TOE and DCC is administered following established local guidelines.

With anaesthesiology assistance (standard care)

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Adult patients (≥18 years) with atrial fibrillation or flutter
• Scheduled for transoesophageal echocardiography-guided direct current cardioversion

You may not qualify if:

• Previous enrolment in the trial
• Expected prolonged hospitalisation (\>8 hours) despite sinus rhythm restoration:
• Ongoing medical needs after cardioversion (e.g., decompensation or infection)
• Planned procedures after cardioversion (same-day TTE or pacemaker test allowed)
• Social barriers for same-day discharge
• Indication for anaesthesiology assistance:
• Haemodynamic instability (systolic blood pressure \<90 mmHg)
• Known severe pulmonary disease (FVC or FEV1 \<50% predicted)
• Body mass index \>40 kg/m2
• Previous complications or allergic reactions to sedation
• Contraindications:
• Pregnant or breastfeeding
• Intracardiac thrombus
• Total benzodiazepine dose used for TOE \>20 mg
• Abbreviations: FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity; TOE, transoesophageal echocardiography; TTE, transthoracic echocardiography.

Sponsors & Collaborators

• Gødstrup Hospital: lead
• University of Aarhus: collaborator

Study Sites (2)

Gødstrup Hospital

Herning, Central Jutland, 7400, Denmark

Location

Randers Regional Hospital

Randers, Central Jutland, Denmark

Location

MeSH Terms

Conditions

Atrial Fibrillation; Atrial Flutter

Condition Hierarchy (Ancestors)

Arrhythmias, Cardiac; Heart Diseases; Cardiovascular Diseases; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: HEALTH SERVICES RESEARCH
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: April 24, 2026
• First Posted: May 6, 2026
• Study Start: May 1, 2026
• Primary Completion (Estimated): May 1, 2027
• Study Completion (Estimated): May 1, 2027
• Last Updated: May 6, 2026

Record last verified: 2026-03

Locations

DK (2)