The Frequency and Risk Factors for Ischemic Stroke in Myotonic Dystrophy Type 1 Patients

Introduction: Patients with myotonic dystrophy type 1 have several cardiac abnormalities, especially myocardial conduction disorders. Few studies have investigated cerebral infarction. We investigated the frequency of both symptomatic and asymptomatic ischemic strokes in patients with myotonic dystrophy type 1. Methods: Patients who were diagnosed with myotonic dystrophy type 1 using genetic testing or clinical examinations at Asahikawa Medical Center were included. We retrospectively reviewed their medical history, neuroradiological imaging, electrocardiograms, and treatment. Their CHADS2 and CHA2DS2-VASc scores were calculated. Result: A total of 108 patients were diagnosed with myotonic dystrophy type 1. Magnetic resonance imaging was performed in 72 and 1 patient whose results were not available was excluded. Among these, 2 patients had atrial flutter and 3 had atrial fibrillation. Regarding the CHADS2 score, 11 patients scored more than 2. Regarding the CHA2DS2-VASc score, 22 patients scored more than 2. Ischemic strokes were found in 9 patients with 1 having an atrial flutter and 4 having atrial fibrillation. All patients with stroke had CHADS2 and CHA2DS2-VASc scores higher than 2. There were significant differences between the 2 groups in atrial fibrillation (P < .001), CHADS2 score (P < .001), and CHA2DS2-VASc score (P < .001). Conclusions: Ischemic stroke in patients with myotonic dystrophy type 1 is associated with atrial fibrillation. The CHADS2 score seems to be useful for the management of patients with myotonic dystrophy type 1. Repeated electrocardiograms are necessary for managing these patients.