潜因性脳梗塞へのアプローチ

抄録

Cryptogenic strokes are now thought to comprise about 25% of all ischemic strokes. These unable to find a precise mechanism of ischemia after standard workup, including transthoracic echocardiography, 12–lead electrocardiogram, inpatient cardiac telemetry monitoring, 24–hour Holter monitoring, magnetic resonance imaging, and a various vascular imaging of neck and brain arteries. Additional investigation identifies a likely mechanism in more than half these patients, such as cancer, aortic complicated lesion, coagulation disorders, et al. Most of cryptogenic strokes are cerebral embolism, arising from proximal arterial sources, heart, and/or venous sources. Embolic strokes of undetermined source are operationally defined as non–lacunar brain infarcts without substantial proximal arterial stenosis or major cardioembolic sources, and they represent 80 to 90% of all cryptogenic strokes. Patent foramen ovale (PFO) is found in up to half of young adults with cryptogenic stroke, and then percutaneous devices for closure of a PFO should be used for them after careful inspection. Occult, low–burden, paroxysmal atrial fibrillation is increasingly recognized as a source of cryptogenic stroke, especially in older patients. Insertable cardiac monitor provides them with an adequate strategy using anticoagulation.