Exclusion of Left Atrial Appendage Thrombus in Emergency Department Patients With Atrial Fibrillation Undergoing CT to Assess for Pulmonary Embolus: A Feasibility Study

N/ANot Yet RecruitingNCT07647939

Northwell Health60 enrolled

Overview

This study aims to investigate whether a quick, additional CT scan of the heart, performed immediately after a standard CT scan for pulmonary embolism, can effectively detect blood clots in the left atrial appendage (LAA) in patients with atrial fibrillation. Detecting these clots is crucial before certain heart procedures to prevent stroke. Currently, a different, more involved procedure (Transesophageal Echocardiography - TEE) is often used. This study will assess if this additional CT scan is feasible, meaning if it can provide clear enough images to identify LAA clots without needing more contrast dye. The study will involve 60 patients, half receiving an "ungated" CT scan and the other half a "gated" CT scan (timed with their heart rhythm). The results of these scans will not be used for immediate patient care during the study, but rather to evaluate the CT scan technique itself. There is no direct benefit to participants, but the information gained could lead to faster diagnosis and reduced unnecessary testing for future patients.

Study Type

INTERVENTIONAL

Allocation

NON_RANDOMIZED

Purpose

DIAGNOSTIC

Masking

SINGLE

Enrollment

Conditions

Atrial Fibrillation (AF)Pulmonary Embolism (PE)Left Atrial Appendage Thrombosis

Interventions

Delayed Un-gated CT Scan for Left Atrial Appendage ThrombusDEVICE

Patients already undergoing CT angiography for suspected pulmonary embolism will receive an additional, delayed un-gated CT scan (60 seconds after initial contrast injection) to assess for LAA clot. No additional intravenous contrast will be given.

Delayed Gated CT Scan for Left Atrial Appendage ThrombusDEVICE

Patients already undergoing CT angiography for suspected pulmonary embolism will receive an additional, delayed gated CT scan (60 seconds after initial contrast injection) to assess for LAA clot. No additional intravenous contrast will be given.

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Patients above 18 years of age years deemed candidates for CT angiography for pulmonary embolism by the primary team on clinical grounds and noted to be in atrial fibrillation at the time. * Room air oxygen saturation above 92% * Systolic blood pressure above 100 mm Hg * Respiratory rate less than 24 breaths/min Exclusion Criteria: * Inability to personally give informed consent * Pregnant or breastfeeding individuals * Stroke like symptoms * ECG criteria for ischemia or infarction * Heart rate \<40 or \> 120 bpm (inclusive) or 3rd degree heart block * Unable to lie flat for at least 10 minutes * Unable to follow simple commands * Northwell Health Employees. * Non-English-speaking patients

Outcomes

Primary Outcomes

Percentage of Indeterminate Left Atrial Appendage (LAA) Thrombus Scans

The primary endpoint of this study is to test the hypothesis that less than or equal to 20% of the repeat CT scan (described above) will be indeterminate for the presence or absence of left atrial appendage thrombus. Additionally, the proportion of indeterminate gated CT scans will be compared to the proportion of indeterminate ungated CT scans.

Time frame: The overall assessment and statistical analysis of this primary outcome for feasibility determination will be conducted at the study completion, an average of one year.

Secondary Outcomes

Diagnostic Accuracy of Repeat CT Scan for Left Atrial Appendage (LAA) Thrombus Detection.

The secondary outcome of this study will be calculation of the negative and positive predictive value of this additional CT scan for detection of left atrial appendage thrombus, in the study population.

Time frame: The secondary outcome will only be calculated at the end of the study (expected date of one year from the first enrollment) if statistically appropriate.