In November 2024, two new RCTs were published that investigated whether atrial fibrillation screening using an ECG is effective. Both showed no significant benefit. Nevertheless, it is recommended in the new ESC guidelines. Why? Here are some insights.
New Study 1: GUARD-AF
- Participants: 12,000 primary care patients (average age 75) in the USA
- Intervention: Screening with a 2-week ECG monitoring vs. standard care
- Outcome: Atrial fibrillation (AF) was diagnosed more frequently in the screening group, and oral anticoagulation was initiated more often, but this did not result in fewer strokes:
New Study 2: STROKESTOP-II
- Participants: All 75- and 76-year-old residents of Stockholm were randomized (29,000 people)
- Intervention: NT-proBNP measurement + 1 ECG for BNP levels under 125 ng/L (in 40% of participants) or daily 4 ECGs for 2 weeks for higher BNP levels (in 60%) vs. standard care
- Outcome: After 5 years, strokes and thromboembolic events were just as frequent despite screening (HR 0.96, 95% CI 0.86-1.06). A limitation was that only 49% of those invited participated in the screening.
What does the new 2024 ESC Guideline recommend?
- Routine heart rhythm assessment during healthcare visits in all aged 65 or older (Class I, Level C)
- Prolonged ECG in all aged 75 or older and in those aged 65 or older with an additional CHA2DS2-VA risk factor (Class IIa, Level B)
This is surprising, as even in the text of the same ESC guideline, it is stated that “there are a lack of adequately powered randomized controlled studies on ischaemic stroke rate in patients screened for AF” and that “population selection that might benefit most from screening … are uncertain.”
How independent is this ESC Guideline?
The German initiative „Leitlinienwatch.de” evaluates medical treatment guidelines for their independence from the pharmaceutical industry. Up to 18 points can be awarded for measures that reduce the influence of conflicts of interest. The current ESC guideline received only 3 out of 18 points from Leitlinienwatch. Deductions were made, among other things, because 90% of the guideline committee members reported an average of 4 conflicts of interest, and the two lead authors together declared 14 conflicts of interest.
Even if one disagrees with the content, ESC guidelines are influential… The older 2020 ESC Leitlinie on atrial fibrillation has been cited over 10,000 times and read more than 2 million times.
What do other Guidelines recommend?
- ACC/AHA/ACCP/HRS Guideline (2023): “It is not yet established that patients at high risk of developing AF by a validated risk score benefit from screening.”
- USPSTF Update (2022): “The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of screening for AF.”
- UK National Screening Committee (2019): “Screening is not currently recommended for this condition.”
- Although not a guideline, still relevant: The German Arznei-Telegramm concluded in 2021, 2023, and 2024 that atrial fibrillation screening is not recommended in asymptomatic individuals.
Conclusion:
- Most guidelines do not recommend atrial fibrillation screening for asymptomatic, older patients.
- Two new studies also show no significant benefit for this approach.
- The new 2024 ESC guideline takes a different view and recommends atrial fibrillation screenings for very large patient groups.
