High Detection Rate of Atrial Fibrillation With Insertable Cardiac Monitor Implantation in Patients With Cryptogenic Stroke Diagnosed by Magnetic Resonance Imaging

BACKGROUND

Detection and treatment of atrial fibrillation (AF) is a major goal in preventing secondary stroke. Insertable cardiac monitors (ICMs) are available for diagnosis of arrhythmia monitoring in patients with cryptogenic stroke. Magnetic resonance imaging (MRI)-based diagnostic evaluation for acute ischemic stroke subtype classification is common in Japan and can be useful for specific diagnosis of cryptogenic stroke.

PURPOSE

We aimed to investigate the detection rate of AF with an ICM in patients with cryptogenic stroke who were diagnosed by MRI.

METHODS

We performed a retrospective, multicenter, observational study. AF monitoring data of an ICM (Reveal LINQ) in patients with cryptogenic stroke were registered from 5 stroke centers in Japan between October 2016 and March 2018. ICM candidates in cryptogenic stroke were diagnosed by MRI-based evaluation and selected according to the criteria proposed by the Japan Stroke Society. Detection of AF was defined as AF for longer than 120 seconds.

RESULTS

Eighty-four consecutive patients (64 men; aged 38-90 years) underwent ICM implantation after diagnosis of cryptogenic stroke. AF was detected in 22 of 84 (26.2%) patients with an ICM during a median follow-up of 221.5 days (range: 93-365 days). The detection rate of AF within 3 months after ICM implantation was 21.4%.

CONCLUSIONS

The AF detection rate with an ICM is approximately one fifth within 3 months in patients with cryptogenic stroke as diagnosed by MRI. Our data suggest that the Japanese criteria based on MRI may be useful for selecting adequate candidates for ICM implantation.