Patent Foramen Ovale (PFO) and Risk of Perioperative Stroke

Study Overview
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Brief Summary
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This is a multi-centre, prospective cohort study to determine if asymptomatic PFO is a risk factor for developing perioperative overt and covert stroke in patients undergoing non-cardiac surgery.

Detailed Description
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There is emerging evidence regarding the increased risk of perioperative stroke in patients with PFO, leading to an important clinical practice question: whether PFO should be considered in the perioperative risk assessment in non-cardiac surgery patients. The evidence base, however, comes from retrospective studies with numerous limitations. Patients referred for general, orthopedic, urological, gynecologic, spinal, or thoracic surgery will be screened and consented during the surgery pre-admission clinic visit, and then undergo PFO screening using transcranial Doppler (TCD) and transthoracic echocardiography (TTE). Patients screened PFO+ (n=102) and matched PFO- controls (n=102) will have DW-MRI between postoperative days 2 and 7. Study personnel will conduct phone surveys at 30-day and 1-year post-surgery to collect data on other clinical outcomes. Patients will also be administered cognitive and patient-reported outcome measures assessments before enrollment, and 30-day and 1-year follow-up.

Official Title
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Canadian Patent Foramen Ovale and Perioperative Stroke Evaluation Study (CAPPRES): A Feasibility Study

Conditions
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Patent Foramen Ovale

Intervention / Treatment
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* Diagnostic Test: Diffusion-weighted Magnetic Resonance Imaging (DW-MRI)
* Diagnostic Test: Transcranial Doppler (TCD)
* Diagnostic Test: Transthoracic Echocardiogram (TTE)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients 18 years and above; referred for an elective, non-cardiac, non-vascular and non-brain surgery; with an estimated hospital length of stay ≥2 days. We will include patients referred for general, orthopedic, urological, gynecologic, spinal or thoracic surgery. Exclusion Criteria: patients in need for long-term, perioperative anticoagulants; those with comorbidities that potentially increase the risk of perioperative stroke; contraindications to MRI; unable to complete or adhere to the study.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 110 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Surgical patients<br>Patients undergoing major non-cardiac, non-vascular, and non-brain surgery who will be examined for a presence of PFO | Diagnostic Test: Diffusion-weighted Magnetic Resonance Imaging (DW-MRI)<br>* The Diffusion-weighted Magnetic Resonance Imaging (DW-MRI) is used to diagnose perioperative stroke.<br>Diagnostic Test: Transcranial Doppler (TCD)<br>* Used to diagnose PFO<br>Diagnostic Test: Transthoracic Echocardiogram (TTE)<br>* Used to diagnose PFO.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Prevalence of PFO in the target (surgical) population | Identifying PFO status using TCD & TTE | Pre-operative | 
| The incidence of perioperative stroke in patients without PFO | Identifying perioperative stroke incidence using DW-MRI | Within 30 days of surgery | 
| Study enrollment rate | Establishing study enrollment rate and the reasons for refusals to participate | Pre-operative | 
| Proportion of patients completing the DW-MRI test | Developing mechanisms to successfully arrange the DW-MRI within a short timeframe | 2-7 days post surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Patent Foramen Ovale, Perioperative Stroke, Diffusion-weighted Magnetic Resonance Imaging