Sinus node dysfunction and stroke risk: a systematic review and meta-analysis

OBJECTIVES: The role of cardiac arrhythmia in ischaemic stroke is widely studied, but the size of the stroke risk in patients with sinus node dysfunction (SND) with and without atrial fibrillation (AF) is unclear. This systematic review and meta-analysis aimed to compare the risk of stroke and its associated factors in patients with SND with and without AF. DESIGN: A systematic review and meta-analysis was conducted based on the Grading of Recommendations, Assessment, Development and Evaluation approach. DATA SOURCES: PubMed, EMBASE and Cochrane Database were searched until December 2022. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Studies that investigate stroke in patients with SND diagnosed with or without AF/atrial flutter. DATA EXTRACTION AND SYNTHESIS: Two independent authors screened studies for inclusion and extracted data. Literature quality assessment was performed using the Newcastle-Ottawa Scale and the Cochrane Collaboration Tool. The overall risk of stroke was estimated using the random-effects model. The generic inverse variance method was used to calculate the pooled estimates of stroke-associated factors. We performed a sensitivity analysis using a fixed-effects model. RESULTS: Of the 929 records retrieved, 6 papers (106 163 patients) met the inclusion criteria. The average yearly stroke incidence in patients with SND was 1.542% (95% CI: 1.334% to 1.749%). The stroke incidence was similar between the isolated SND (1.587%; 95% CI: 1.510% to 1.664%) and non-isolated (SND+AF) (1.660%; 95% CI: 0.705% to 2.615%) groups. AF (HR, 95% CI: 1.53 (1.01 to 2.33)), stroke/transient ischaemia attack/other thrombotic events (HR, 95% CI: 2.54 (1.14 to 5.69)), hypertension (HR, 95% CI: 1.51 (1.11 to 2.07)) and heart failure (HR, 95% CI: 1.41 (1.01 to 1.97)) were associated with stroke in the SND population. CONCLUSION: Our findings suggest that patients with SND carry a similar risk of stroke to those with combined SND and AF. Future studies are needed to investigate whether interventions targeting stroke prevention, such as anticoagulation therapy, can help to prevent stroke in patients with SND. PROSPERO REGISTRATION NUMBER: CRD42023408436.