None listed
Conditions
Brief summary
Function of the cardiac left atrial chamber is known to be impaired in people with atrial fibrillation, a condition principally related to this structure. In people who have an ischaemic stroke, roughly one quarter will have no definite cause found despite extensive imaging and other tests, though up to 30 percent of these will have atrial fibrillation diagnosed on implantable cardiac monitoring in the 3 years after stroke. The purpose of this study is to determine if a proportion of this group with stroke of undetermined source have signs of left atrial cardiomyopathy, evidenced by low left atrial reserve at rest and during exertion seen on echocardiographic imaging, and if this is reflected by impaired exercise tolerance, altered blood test biomarkers, or left atrial structure and epicardial fat abnormalities on computed tomography.
Interventions
Observational
This study will evaluate left atrial structure and function in participants who have experienced embolic stroke of undetermined source, compared with participants who have a history of atrial fibrillation, and a group who have no history of either of these conditions. Participants will have a one-off measurement of parameters within 12 months of embolic stroke or atrial fibrillation diagnosis. Measurements will be performed during recruitment between July 2020 and July 2023.
Left
Observational This study will evaluate left atrial structure and function in participants who have experienced embolic stroke of undetermined source, compared with participants who have a history of atrial fibrillation, and a group who have no history of either of these conditions. Participants will have a one-off measurement of parameters within 12 months of embolic stroke or atrial fibrillation diagnosis. Measurements will be performed during recruitment between July 2020 and July 2023. Left atrial function will be evaluated through resting and exercise echocardiographic imaging of left atrial emptying fraction, dimensions and strain parameters. Exercise capacity will be evaluated through cardiopulmonary exercise testing utilising a standardised bicycle protocol and metabolic cart. Left atrial and cardiac structure will be evaluated through CT imaging of left atrium, pulmonary veins and epicardial adipose tissue.
Sponsors
University of Adelaide
Eligibility
Sex/Gender
All
Age
18 Years to 85 Years
Healthy volunteers
Yes
Inclusion criteria
At least 18 years old Embolic Stroke of Undetermined Source (ESUS) subgroup - history of ESUS Atrial Fibrillation (AF) subgroup - history of AF Comparison group - no history of either of these conditions (AF or ESUS)
Exclusion criteria
• Age > 85 years • Pregnancy or planned pregnancy within the next 24 months • Unable to undergo MRI scan • Major Surgery <6 months • Valvular Disease Needing Intervention • LVEF equal to or less than 35% • Active Malignancy • Autoimmune or Systemic Inflammation • Specific Stroke Mechanisms: Patent Foramen Ovale, Vessel Dissection, Subacute Bacterial Endocarditis • Severe Renal Dysfunction (defined as dialysis, prior or planned transplant, Cr >2.26 mg/dl or > 200 µmol/L) • Severe Liver Dysfunction (Cirrhosis or Bilirubin > 2 x Normal or AST/ALT/ALP > 3x Normal) • Malabsorption Disorders • Institutional Living • Inability to Attend Appointments • Inability to Provide Informed Consent
Outcome results
None listed