"Atrial fibrillation detection after stroke". The New England Journal of Medicine. 2014. PubMed • Full text • PDF

Contents

1 Clinical Question
2 Bottom Line
3 Major Points
4 Guidelines
5 Design
6 Population
6.1 Inclusion Criteria
6.2 Exclusion Criteria
6.3 Baseline Characteristics
7 Interventions
8 Outcomes
8.1 Primary Outcomes
8.2 Secondary Outcomes
9 Funding
10 Further Reading

Clinical Question

Does noninvasive ambulatory electrocardiographic (ECG) monitoring for 30 days significantly improve the detection of atrial fibrillation in patients over 55 with recent cryptogenic stroke or transient ischemic attack (TIA), compared to conventional 24-hour ECG monitoring?

Bottom Line

In patients over 55 with recent cryptogenic ischemic stroke or TIA, 30-day noninvasive ambulatory ECG monitoring was superior to a conventional 24-hour monitor in detecting atrial fibrillation and increased anticoagulation therapy for secondary prevention of stroke.

Major Points

Guidelines

No updated guidelines reflecting this trial were cited.

Design

- Multicenter, randomized, open-label trial
- N=572 patients with cryptogenic ischemic stroke or TIA
- Intervention: Noninvasive ambulatory ECG monitoring with a 30-day event-triggered recorder (n=280)
- Control: One additional round of 24-hour Holter monitoring (n=277)
- Enrollment: 2009-2012
- Mean follow-up: 90 days
- Analysis: Intention-to-treat
- Primary outcome: Newly detected atrial fibrillation lasting 30 seconds or longer within 90 days after randomization

Population

Inclusion Criteria
- Age ≥55 years
- No known atrial fibrillation
- Had a cryptogenic ischemic stroke or TIA within the previous 6 months
- Undetermined cause after standard workup including 24-hour ECG

Exclusion Criteria
- Known causes of stroke such as large-vessel or small-vessel disease
- Age <55 years

Baseline Characteristics
- Mean age: 72.5±8.5 years (range, 52 to 96)
- 62.9% had ischemic stroke, 36.9% had a TIA
- Median CHADS2 score: 3 points (range, 2 to 6)

Interventions

- Participants were randomly assigned to either 30-day event-triggered ECG recording or a single additional 24-hour Holter ECG recording.

Outcomes

Primary Outcomes
- Atrial fibrillation lasting 30 seconds or longer was detected in 16.1% of the intervention group vs. 3.2% of the control group within 90 days (P<0.001)

Secondary Outcomes
- Oral anticoagulant therapy at 90 days was prescribed in 18.6% of the intervention group vs. 11.1% of the control group (P=0.01)
- Atrial fibrillation lasting 2.5 minutes or longer detected in 9.9% of the intervention group vs. 2.5% of the control group (P<0.001)
- Compliance with ECG monitoring was also evaluated.

Funding

Supported by peer-reviewed operating grants from the Canadian Stroke Network and others.

Further Reading