STROKE-AF 3-Year
(2023)Objective
To compare the rates of atrial fibrillation detection through 3 years of follow-up between an insertable cardiac monitor (ICM) vs usual care in patients with prior ischemic stroke attributed to large-artery atherosclerotic disease (LAD) or small-vessel occlusive disease (SVD)
Study Summary
• 87% of AF detected at 3 years would have been missed with only 30 days of monitoring
• Patients with CHF, LAE, BMI >30, or QRS >120ms had 4-fold higher AF detection (30% vs 8.6%)
Intervention
Insertable cardiac monitor (REVEAL LINQ) vs site-specific usual care
Inclusion Criteria
Patients ≥60 years (or 50-59 with additional stroke risk factors) with ischemic stroke attributed to large- or small-vessel disease (TOAST criteria) within 10 days of enrollment
Study Design
Arms: ICM group vs Control group (usual care)
Patients per Arm: ICM: 242, Control: 250
Outcome
• AF progression: 12.5% at 1 year → 18.5% at 2 years → 21.7% at 3 years in ICM group
• Recurrent stroke: 17.0% ICM vs 14.1% control (HR 1.1, P=0.71, NS)
Bottom Line
In patients with ischemic stroke attributed to LAD or SVD, the risk of AF detection continues to rise beyond 1 year, reaching 21.7% at 3 years with ICM monitoring vs only 2.4% with usual care (HR 10.0). Most AF episodes are asymptomatic and would be missed by standard intermittent monitoring. One year of negative monitoring should not reassure clinicians that patients will not develop AF over subsequent years.
Major Points
- At 3 years, AF was detected in 21.7% of ICM patients vs 2.4% of controls (HR 10.0, 95% CI 4.0-25.2, P<0.001)
- AF detection increased progressively: 2.6% at 1 month, 7.9% at 6 months, 12.5% at 12 months, 18.5% at 2 years, 21.7% at 3 years
- 87% of AF detected at 3 years would have been missed with only 30 days of continuous monitoring
- 88% of all AF episodes in the ICM group were asymptomatic
- 67.4% of patients with AF had at least one episode lasting >1 hour; median longest episode was 176 minutes
- AF burden progressed over time: 66% of patients with ≥6 minutes of AF had burden progression
- Patients with CHF, LAE, BMI >30, or QRS >120ms had 4-fold higher AF detection (30.0% vs 8.6%, HR 4.1)
- OAC prescription was higher in ICM group: 24.4% vs 8.0% (OR 3.7, P<0.001)
- Recurrent stroke rates were similar: 17.0% ICM vs 14.1% control (HR 1.1, P=0.71)
- 24% of patients with detected AF in ICM group were not anticoagulated
Study Design
- Study Type
- Randomized controlled trial, multicenter, parallel-group, open-label (prespecified long-term secondary outcome analysis)
- Randomization
- Yes
- Blinding
- Open-label; not feasible due to nature of intervention
- Sample Size
- 492
- Follow-up
- Up to 3 years (through July 2022); mean follow-up 29.4 months
- Centers
- 33
- Countries
- United States
Primary Outcome
Definition: Time to first detection of atrial fibrillation (episode lasting >30 seconds, adjudicated by Clinical Events Committee) through 3 years of follow-up (prespecified secondary outcome of original trial)
| Control | Intervention | HR/OR | P-value |
|---|---|---|---|
| 2.4% (5 patients) | 21.7% (46 patients) | 10 (4.0 to 25.2) | <0.001 |
Limitations & Criticisms
- Treatment for AF was neither randomized nor prescribed by study protocol, limiting conclusions about clinical impact
- Reasons for OAC use/nonuse were not captured
- Study was not powered to detect differences in recurrent stroke rates
- 24% of patients with detected AF were not anticoagulated, limiting potential clinical benefit
- Presumed etiology of index and recurrent stroke was determined by site investigators, not centrally adjudicated
- Control group did not include recently approved noninvasive wearable devices for AF detection
- Cannot exclude that some AF detected represents background asymptomatic AF unrelated to stroke
- Clinical significance of short AF episodes (minutes long) remains uncertain
- 36.2% of patients did not complete 3-year follow-up
Citation
JAMA Neurol. 2023;80(12):1277-1283