https://doi.org/10.1007/s00392-024-02526-y
1Klinikum rechts der Isar der Technischen Universität München Klinik und Poliklinik für Innere Medizin I München, Deutschland; 2Herzzentrum Alter Hof Gemeinschaftspraxis für Kardiologie und Nuklearmedizin München, Deutschland; 3Mediclin MVZ Praxis für Kardiologie und Angiologie Dessau-Roßlau, Deutschland
Background:
Undiagnosed atrial fibrillation (AF) significantly increases neurovascular and cardiovascular risks. Early AF detection is crucial for initiating appropriate treatments in at-risk individuals, thereby improving outcomes. An implantable loop recorder (ILR) monitors heart rhythm for up to three years, with advanced devices featuring specialized AF detection algorithms. However, real-world studies on the use of ILRs for AF detection in patients with a history of cryptogenic stroke (CS) are limited.
Objective:
This study investigates whether office-based cardiologists' use of ILRs increases AF detection rates in patients with recent cerebrovascular events who present in sinus rhythm and have no prior history of AF.
Method:
The SPIDER-AF registry is a non-interventional, multicentric, observational study conducted across 34 private cardiology practices and one clinic in Germany. It included outpatients with no prior AF history who experienced a cryptogenic stroke (CS) or presumed thromboembolic transient ischemic attack (TIA) within the past 12 months.
Results:
A total of 500 patients were examined in real-world settings after a cryptogenic stroke and subsequent implantation of a Reveal LINQ event recorder. The average age was 63.1 ± 12.7 years, with 60.8% men and 39.2% women. The qualifying event was TIA in 27.4% and stroke with a typical thromboembolic pattern on cerebral imaging in 72.6%. All participants were observed for at least 12 months post-inclusion. AF was detected in 133 patients (Total 26.8%, TIA 29.9% vs. stroke 25.3%, P=ns) after a median of 121.5 days. AF was primarily paroxysmal (95.7% after stroke, 100% after TIA). The average duration of an episode was 146.4 minutes (minimum duration 30 seconds). 52.7% of patients had 1-2 episodes, 19.1% had 3-10 episodes, 12.2% had up to 50 episodes, and 7.6% had more than 50 episodes during the observation period (Figure 1). In 19.5% of cases, anticoagulation was not administered post-AF detection. Typical cardiovascular risk factors were similar in both groups except for diabetes, which was higher in patients with stroke (TIA 15.3% vs. stroke 25.1%, p ≤ 0.022). There was no gender-specific difference in the frequency of detected atrial fibrillation.
Primary comorbidities (CHA2DS2-VASc Score) determined the risk of AF in TIA or stroke. The mean CHA2DS2-VASc score in patients with AF was 4.0 (TIA) and 4.1 (stroke); for those in sinus rhythm, it was 3.7 and 3.9, respectively.
Conclusion:
Integrating telemedical tools like ILRs into routine clinical practice is essential, as ILRs enable early AF detection in patients with an index event such as stroke or TIA in sinus rhythm. Even short episodes of AF and a high CHA2DS2-VASc score indicate an elevated risk of neurovascular events for both TIA and stroke. Therefore, the implantation of an ILR should be considered not only in patients with stroke but also after TIA in sinus rhythm to detect unknown AF and plan anticoagulation therapy.