Left Atrial Imaging Prior to Cardioversion: Leveraging Computed Tomography to Rule Out Thrombus in The Emergency Department (LA CLOTTED)
Ottawa Heart Institute Research Corporation
190 participants
Jun 15, 2025
INTERVENTIONAL
Conditions
Summary
The goal of this randomized clinical trial is to learn whether patients with symptomatic atrial fibrillation or atrial flutter (AF) who require heart imaging to rule out a blood clot before cardioversion would benefit from cardiac computed tomography angiography (CCT) in the emergency department (ED) compared to current standard of care management. This will be a multicenter trial evaluating whether CCT-facilitated cardioversion in the ED reduces hospital admission, reduces repeat presentations to hospital and improves patient quality of life compared to the current standard of care. Participants will undergo CCT-facilitated cardioversion or be treated according to current standard of care while in the ED and complete quality of life questionnaires in the ED and follow-up at 30 days.
Eligibility
Inclusion Criteria3
- Age ≥18 years old; and
- Primary symptomatic AF without a reversible underlying cause (e.g. sepsis, pneumonia, pulmonary embolism, hyperthyroidism)
- LA imaging required before cardioversion according to local clinical practice guidelines
Exclusion Criteria2
- Patients with an indication for emergency cardioversion (e.g. hemodynamic instability (systolic blood pressure<90mmHg or signs of shock), cardiac ischemia (ongoing severe chest pain or marked ST depression on ECG >2mm), or pulmonary edema (significant dyspnea, crackles, or hypoxia)); or
- Contraindication to CCT (renal insufficiency (eGFR< 45ml/min/1.73m2), allergy to intravenous contrast agents, pregnancy (contraindications to radiation exposure), or inability to perform 20-second breath-hold)
Interested in this trial?
Get notified about updates and connect with the research team.
Interventions
Patients will undergo CCT according to the following protocol. A non-contrast enhanced prospective ECG-triggered image will be acquired followed by a contrast-enhanced prospective ECG-triggered image using a tri-phasic contrast protocol. Delayed CT images 60 seconds after the initial contrast-enhanced CT scan will be obtained. Cardiac CT image interpretation will be performed according to routine clinical practices in a pragmatic fashion. The LA will be assessed for filling defects and characterized based upon attenuation values. If LA thrombus cannot be excluded, filling defects will be assessed on the delay images. Increases in attenuation would be consistent with pseudo-thrombus from 'slow flow' and 'incomplete opacification'. Areas where attenuation does not change significantly (persistent filling defect) will be diagnosed as thrombus. If the CCT shows no LA thrombus then the ED physician will be able to perform electrical and/or chemical cardioversion at their discretion.
Patients in the standard of care arm may undergo any combination of the following management strategies in the emergency department (ED) at the discretion of their treating physician: 1\. Transesophageal echocardiogram (TEE) facilitated cardioversion; 2. Rate control; 3. Consultation with inpatient cardiac specialist for assessment/management and consideration of hospital admission; 4. cardioversion after 3 weeks of anticoagulation; and/or 5. Outpatient referral to cardiac specialist or general practitioner for further management.
Locations(1)
View Full Details on ClinicalTrials.gov
For the most up-to-date information, visit the official listing.
NCT07002450