A recent study presented at the European Society of Cardiology congress has revealed that mass screening for atrial fibrillation (AF) using electrocardiography (ECG) combined with a heart failure biomarker does not effectively prevent ischemic stroke or systemic embolism in older adults aged 75-76 over a five-year period. However, the biomarker identified may assist in predicting which individuals have a low risk of these events, surpassing the information provided by single-lead ECG alone among older adults undergoing AF screening.
Lead author Katrin Kemp Gudmundsdottir from the Karolinska Institute stated that while the research does not endorse systematic AF screening in older adults, it implies that screening might not need to be directed toward individuals with low levels of NT-proBNP, a biomarker indicative of heart failure. The study indicated that individuals with low NT-proBNP levels exhibited a decreased risk of developing AF during the follow-up period, along with a lower incidence of stroke or systemic embolism compared to both the control group and those with higher biomarker levels.
Currently, international guidelines advocate opportunistic screening for AF in individuals aged 65 and above, recommending oral anticoagulant treatment for those identified as high-risk for stroke. The ESC suggests that systematic ECG screening should be performed in patients aged 75 or older, or those deemed at high risk. The incorporation of biomarkers like NT-proBNP is posited to enhance screening accuracy, as it has been strongly correlated with the likelihood of incident AF and stroke.
The STROKESTOP II trial, which took place in the Stockholm region, involved a mass screening initiative targeting all residents aged 75-76. The study enrolled 28,712 individuals born between 1940 and 1941 to determine whether screening invitations would lead to a reduction in thromboembolic events compared to a control group that was not invited to participate.
Participants were randomly assigned either to be invited for AF screening or to a control group. Among the 13,905 patients invited, approximately 49% accepted, with about 53% of them being women. Those without known AF had their NT-proBNP levels analyzed and were classified into low-risk and high-risk categories based on these levels. High-risk participants underwent intensive home monitoring using a handheld ECG device, while low-risk individuals received a single screening session.
Ultimately, new AF cases were detected in 2.4% of participants who were then offered oral anticoagulants. After a median follow-up of five years, both the intervention group and the control group showed no significant difference in stroke or clotting event risks.
Further analysis indicated a 41% lower risk of stroke or clots among participants with low NT-proBNP levels compared to the control group. Conversely, those in the high-risk category experienced more than double the likelihood of new AF development over five years and a 57% increased risk of ischemic stroke or systemic embolism compared to low-risk individuals.
Kemp Gudmundsdottir remarked on the lower-than-expected participation in the study, suggesting that this may have impacted the results. She recommended that additional research is necessary and advised a focus on high-risk individuals to potentially reduce the incidence of preventable strokes.