Sick sinus syndrome elevates stroke risk in patients with atrial fibrillation with low CHA2DS2-VASC score.
Journal
Heart rhythm
Journal Volume
23
Journal Issue
4
Start Page
e659
End Page
e665
ISSN
1556-3871
Date Issued
2026-04
Author(s)
Abstract
Atrial fibrillation (AF) and isolated sick sinus syndrome (SSS, without AF) are both associated with increased stroke risk. Although AF and SSS often co-exist as tachy-bradyarrhythmia, the impact of SSS on stroke risk among patients with AF remains unclear.
The aim of this study was to evaluate whether SSS is independently associated with incident ischemic stroke in patients with AF. We analyzed a hospital-based cohort of 24,960 patients with AF from 2010 to 2021. SSS was defined strictly as symptomatic sinus node dysfunction requiring pacemaker implantation. The primary end point was ischemic stroke hospitalization. Cox models adjusted for CHADS-VASc (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, stroke or transient ischemic attack, vascular disease, age 65 to 74 years, sex category) score were used to assess associations. Of the 24,960 patients with AF, 1624 had SSS and a pacemaker, whereas 23,336 did not. Patients with SSS were older, more often female, and had higher CHADS and CHADS-VASc scores. Over a mean follow-up of 4.07 ± 3.55 years, stroke incidence was 4.02% per patient-year in the SSS group vs 3.03% in the non-SSS group (P < .001). After adjustment, SSS was associated with a 23% higher stroke risk (hazard ratio [HR] 1.23, 95% confidence interval [CI] 1.10-1.37, P < .001). This association was strongest in patients with CHADS-VASc scores ≤2 (HR 2.13, 95% CI 1.76-2.58, P < .001), but not significant in those with scores >2 (HR 1.02, 95% CI 0.89-1.17, P = .722). SSS independently predicts higher stroke risk in patients with AF, particularly among those with lower baseline CHADS-VASc scores. This finding may help refine stroke prevention strategies.
The aim of this study was to evaluate whether SSS is independently associated with incident ischemic stroke in patients with AF. We analyzed a hospital-based cohort of 24,960 patients with AF from 2010 to 2021. SSS was defined strictly as symptomatic sinus node dysfunction requiring pacemaker implantation. The primary end point was ischemic stroke hospitalization. Cox models adjusted for CHADS-VASc (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, stroke or transient ischemic attack, vascular disease, age 65 to 74 years, sex category) score were used to assess associations. Of the 24,960 patients with AF, 1624 had SSS and a pacemaker, whereas 23,336 did not. Patients with SSS were older, more often female, and had higher CHADS and CHADS-VASc scores. Over a mean follow-up of 4.07 ± 3.55 years, stroke incidence was 4.02% per patient-year in the SSS group vs 3.03% in the non-SSS group (P < .001). After adjustment, SSS was associated with a 23% higher stroke risk (hazard ratio [HR] 1.23, 95% confidence interval [CI] 1.10-1.37, P < .001). This association was strongest in patients with CHADS-VASc scores ≤2 (HR 2.13, 95% CI 1.76-2.58, P < .001), but not significant in those with scores >2 (HR 1.02, 95% CI 0.89-1.17, P = .722). SSS independently predicts higher stroke risk in patients with AF, particularly among those with lower baseline CHADS-VASc scores. This finding may help refine stroke prevention strategies.
Subjects
Atrial fibrillation
Ischemic stroke
Pacemaker
Sick sinus syndrome
Tachy-bradyarrhythmia
SDGs
Type
journal article