Uncovering Atrial Fibrillation Beyond Short-Term Monitoring in Cryptogenic Stroke Patients

Abstract

Background— Atrial fibrillation (AF) can be a cause of previously diagnosed cryptogenic stroke. However, AF can be paroxysmal and asymptomatic, thereby making detection with routine ECG methods difficult. Oral anticoagulation is highly effective in reducing recurrent stroke in patients with AF, but its initiation is dependent on the detection of AF. Cryptogenic Stroke and Underlying Atrial Fibrillation (CRYSTAL AF) is the first randomized study to report the detection of AF in cryptogenic stroke patients using continuous long-term monitoring via insertable cardiac monitors (ICM). Methods and Results— Patients with prior cryptogenic stroke were randomized to control (n=220) or ICM (n=221) and followed for ≤36 months. Cumulative AF detection rates in the ICM arm increased progressively during this period (3.7%, 8.9%, 12.4%, and 30.0% at 1, 6, 12, and 36 months, respectively), but remained low in the control arm (3.0% at 36 months). This resulted in oral anticoagulation prescription in 94.7% of ICM patients with AF detected at 6 months, 96.6% at 12 months, and 90.5% at 36 months. Among ICM patients with AF detected, the median time to AF detection was 8.4 months, 81.0% of first AF episodes were asymptomatic, and 94.9% had at least 1 day with >6 minutes of AF. Conclusions— Three-year monitoring by ICM in cryptogenic stroke patients demonstrated a significantly higher AF detection rate compared with routine care. Given the frequency of asymptomatic first episodes and the long median time to detection, these findings highlight the limitations of using traditional AF detection methods. The majority of patients with AF were prescribed oral anticoagulation therapy. Clinical Trial Registration— Clinicaltrials.gov ; Unique identifier: NCT00924638.

Refinement of detecting atrial fibrillation in stroke patients: results from the TRACK‐AF Study

“…The randomized CRYSTAL AF study [19] demonstrated an AF detection rate of 12.4% within a monitoring period of 12 months. Thus, monitoring with an ICM leads to an eightfold higher detection rate of AF than using conventional methods [19,20]. The 18% AF detection rate in our study is in line with previous studies bearing in mind the longer monitoring period of 20 months.…”

“…Besides, numerous studies found increased detection rates of AF by ICM leading to ICM as the current standard of occult AF detection after cryptogenic stroke in many centres. The main advantage of ICM obviously is the long-term monitoring period, as in many cases AF is detected after a 30-day monitoring period [16][17][18][19][20]. Hindricks et al [16] reported a sensitivity of 96.1%, a specificity of 85.4%, a PPV of 79.3% and an NPV of 97.4% in detecting pAF.…”

Atrial time and voltage dispersion are both needed to predict new-onset atrial fibrillation in ischemic stroke patients

“…The impact of ischemic stroke on the risk of subsequent development of AF is only beginning to become clear [2, 3]. Information on development of new AF in ischemic stroke patients using ECG monitoring has been seldom reported until recently [4–6]. Clinical cardiovascular risk scoring tools such as the CHADS 2 and CHA 2 DS 2 -VASc have demonstrated association with development of first-ever AF during 2-year and 10-year follow-up time frames in recent studies [7–9].…”

Developing and Sustaining a Career as a Transdisciplinary Nurse Scientist

“…The ongoing research conducted by nurse scientists continues to play an influential role in helping individuals recognize, manage and alleviate their symptoms. One important issue related to AF is the difficulty of diagnosing and detecting AF, particularly when the patient is asymptomatic or may simply ignore symptoms such as fatigue and assume such symptoms are “normal” age related changes (Brachmann, et al, 2016). Additionally, symptoms of AF can mimic symptoms associated with other cardiac and non-cardiac underlying conditions (Hickey, et al, 2016).…”