Introduction: Cryptogenic stroke (CS) accounts for 30–40% of all ischaemic strokes and there is substantial evidence to suggest arrhythmogenic cardioembolic involvement following the development of atrial fibrillation (AF). CS related to AF are often devastating, with around 70% mortality or significant disability. CS recurrence in the context of AF can be reduced with initiation of anticoagulation therapy. AF can occur in paroxysms and may not always be present at the time of stroke presentation and therefore go undetected with 12-lead ECG monitoring. Traditionally, ambulatory monitoring was used to detect AF post CS; however, CRYSTAL-AF demonstrated that prolonged cardiac rhythm monitoring using an implantable loop recorder (ILR), can uncover a substantial proportion of stroke patients with AF that would otherwise not be detected by conventional short-term ambulatory monitoring. A clear multidisciplinary pathway has been established at University Hospital of North Midlands for CS patients to access ILR monitoring.
Aims: The aim of this study is to determine the diagnostic yields for the detection of AF following CS, when using ILRs compared to ambulatory monitoring.
Objectives:
- Calculate the incidence of AF detection post-CS with the utilization of ILRs.
- Calculate the incidence of AF detection post-CS with the utilization of ambulatory monitoring.
- Calculate the difference in AF detection post-CS with the utilization of ILRs when compared to ambulatory monitoring.
Methods: A retrospective observational study was conducted in a single tertiary centre in the UK. Local electronic dating reporting systems were used to review baseline characteristics and clinical outcomes between January and December 2021.
Results: A total of 843 patients underwent post-CS monitoring for the detection of AF. Seven hundred and forty-one patients received ambulatory monitoring of up to 72 hours in duration. One hundred and two patients received an ILR, and a positive diagnostic yield of atrial fibrillation was detected in 28 patients with ambulatory monitoring (3.78%) and 16% of patients in the ILR group (p=<0.001).
Conclusion: This study provides an up-to-date review of contemporary practice in the detection of AF post CS, and supports the findings of the existing literature that ILRs significantly increase the detection of AF post CS, when compared with conventional ambulatory monitoring. ❑
