Heterogeneity in Ischaemic Stroke Diagnostic Classification and Cardiac Monitoring Between the United Kingdom and United States: DiVERT Stroke Sub-study.

Abstract

Introduction: The approach to diagnostic classification of ischaemic strokes and post-stroke cardiac monitoring to detect occult atrial fibrillation (AF) differs among healthcare facilities within the United States (US), as shown in the DiVERT Stroke (SeconDary Stroke PreVEntion ThRough Pathway ManagemenT) study. The degree of international neuro-cardio pathway heterogeneity, specifically among the US and the United Kingdom (UK), has not been studied previously.

Methods: We conducted a retrospective review of consecutive patients with cryptogenic, large-vessel disease (LVD), and small-vessel disease (SVD) ischaemic strokes at large, certified stroke centres in the US and UK. Qualitative assessments included stroke aetiology determination and post-stroke cardiac monitoring frequency by methodology.

Results: Between 2017 and 2020, we identified 881 stroke patients within the UK (189) and US (692) respectively, with significant differences in aetiological classification for cryptogenic (50.8% vs. 33.1%, p<0.001) and LVD (16.9% vs. 37.0%, p<0.001), but not for SVD strokes (32.3% vs. 29.9%, p=0.532). Insertable cardiac monitors (ICM) were significantly less utilised for UK versus US patients (5.9% vs. 10.6%, p=0.049); however, external monitor utilisation (68.8% vs. 66.9%, p=0.628) was similar. Correspondingly, AF was diagnosed significantly less in the UK (1.5% vs 7.5%, p=0.012).

Conclusion: Among hospitalised ischaemic stroke patients at comprehensive stroke centres in the US and UK, significant differences exist in aetiological classification, cardiac monitoring and subsequent AF diagnosis. Larger Anglo-American studies may confirm this finding, identify disparities in care, and standardise neuro-cardio pathways internationally to improve outcomes.