卵円孔開存および子宮筋腫による多発性脳塞栓症の1例

Multiple Cerebral Embolism Caused by a Patent Foramen Ovale and a Uterine Myoma

要旨　卵円孔開存と子宮筋腫が反復性脳塞栓症の原因となったと考えられる40歳女性例を報告した。左島皮質の梗塞による右片麻痺と失語に続き，23日後には右視床と右前頭葉深部白質に新たな梗塞を生じた。新生児頭大の子宮筋腫を認め，経食道心エコーにより，卵円孔開存とValsalva手技での右左シャントが証明された。下肢静脈造影，骨盤造影X線CTにて右外腸骨静脈の著明な圧排，造影の途絶が認められ，子宮筋腫に二次的に生じた深部静脈血栓が塞栓源と考えた。近年，経食道心エコーの普及により，若年性脳梗塞の原因として卵円孔開存の重要性が広く認識されるようになった。子宮筋腫の静脈圧排により形成される深部静脈血栓は，卵円孔開存における塞栓源として重要と考えられた。

Recently, patent foramen ovale（PFO）has been highlighted as an important risk factor of cerebral infarctions in young adults. We report a patient of multiple cerebral embolism associated with PFO and deep venous thrombosis caused by a uterine myoma. A 40-year-old woman suddenly suffered from right hemiparesis with motor aphasia. Brain angiography showed an occlusion of M2 portion of the left middle cerebral artery, but atherosclerotic changes were not seen. She developed left facial paresis 23 days later and admitted to our hospital. Brain MRI revealed multiple cerebral infarcts in the left insular cortex, the deep white matter of the right frontal lobe, and bilateral thalamus. Hypoxia with the perfusion defects of S1 and S2 sections of the right lung demonstrated by scintigraphy suggested pulmonary embolism. Transesophageal echocardiography showed a PFO with spontaneous left-to-right shunt and right-to-left shunt evoked by the Valsalva maneuver. Although venography could not detect thrombi, it revealed severe compression of the right external iliac vein by a uterine myoma. These findings suggested thrombi in the right external iliac vein were the embolic source when combined with elevated coagulation markers. An uterine myoma should be considered as an important risk factor for an embolic source in case of cerebral embolism with PFO.