Due to copyright issues, an electronic copy of the thesis must be ordered from the faculty. For the faculty to have time to process the order, the order must be received by the faculty at the latest 2 days before the public defence. Orders received later than 2 days before the defence will not be processed. After the public defence, please address any inquiries regarding the thesis to the candidate.
Trial Lecture – time and place
See Trial Lecture.
Adjudication committee
- First opponent: Professor Ana Catarina Fonseca, Lisbon School of Medicine, University of Lisbon, Portugal
- Second opponent: Professor Maja-Lisa Løchen, UiT - The Arctic University of Norway, Tromsø
- Third member and chair of the evaluation committee: Professor II Bjørnar Hassel, University of Oslo
Chair of the Defence
Professor II Erik Taubøll, University of Oslo
Principal Supervisor
Chief Consultant Anne Hege Aamodt, Oslo University Hospital, Rikshospitalet
Summary
The best treated stroke is the one we have prevented. To achieve this goal optimal secondary prevention must be tailored to the underlying cause. Knowing the aetiology makes it possible to treat patients following the evidence-based medicine principle and successfully prevent new ischaemia.
The current knowledge suggests that atrial fibrillation could be suspected in a substantial proportion of cryptogenic stroke. Transient arrhythmia can however easily be missed under the short-term monitoring in the acute phase, exposing patient to an unnecessary risk of recurrent stroke.
The aim of this thesis was to investigate the burden of atrial fibrillation and clinical predictors of the arrhythmia in cryptogenic stroke patients monitored with insertable cardiac monitor (ICM) for 12 months, as well as the spectrum of other probable or possible underlying stroke causes. The NOR-FIB study was an international, multicentre, prospective, observational trial conducted between January 2017 and September 2021 and finally included 259 patients.
Systematic atrial fibrillation screening with ICM detected atrial fibrillation in almost one in three patients previously classified as cryptogenic. Overall, extended diagnostic work-up and reassessment of the initial findings performed within the first year after stroke and TIA resulted in revealing underlying cause in nearly one in two patients initially labelled as cryptogenic. Uncovering the specific aetiology led to improvement of patient’s secondary prevention lowering the risk of stroke recurrence.
Our findings suggest that a thorough diagnostic evaluation is essential in determining pathogenesis of cryptogenic ischaemic events and securing optimal preventive treatment. Furthermore, the use of ICM was proven manageable for stroke physicians and seems feasible to be implemented in the arrhythmia detection pathway in stroke units.
Additional information
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