訪問：張誠謙心臟科醫生
（一）什麼是卵圓孔未閉症？卵圓孔未閉症與中風有關？
卵圓孔是每個人都有的心臟結構，位於左心房和右心房之間的一道小門。有些情況身體有機會形成血塊，特別在靜脈系統當中。當血塊出現在腿部靜脈系統，便會隨著血流運送到心臟。如果正常卵圓孔關閉，這些血塊會流入肺部作為隔濾，但如果患者有卵圓孔未閉症，血塊便會經由右心房通過卵圓孔到達左心房，隨著血流運送全身，如果血塊去到腦血管，便會形成阻塞，造成缺血性中風。
（二）如何診斷卵圓孔未閉症？
在超聲波檢查中，醫生會放置顏色，看看會否有不正常的血流。就像這個病人的個案，他的右心房和左心房中間有不正常的血流，因此懷疑病人有卵圓孔未閉症。
（三）微創手術如何關閉卵圓孔？
透過X光片段錄影的微創導管封閉卵圓孔手術過程，醫生會在病人大腿股溝切一個很小的傷口，利用一條長導管，由大腿股溝靜脈上到病人右心臟。在X光和超聲波機指引下，導管就會穿過卵圓孔，接着在導管中，醫生會引入封堵器到病人左邊心臟。
過程首先會在左邊心房慢慢放置左心房心碟，然後放置右碟，在X光和超聲波指引下，醫生會把整個系統慢慢拉後，當左碟慢慢去到卵圓孔位置，醫生便會放置封堵器的右碟，封堵器便會永久而穩固地放置在卵圓孔上。
完成後，醫生會將封堵器和導管脫離，讓導管和鋼絲慢慢分離，離開身體，只有封堵器永久植入病人身體。
（四）封堵器如何減低中風風險？
從影片中的食道超聲波影像，可以看到為病人置放封堵器後半年後所錄得的影像從影像可見，封堵器已永久植入在病人卵圓孔上，位於左右心房中間。醫生在檢查時亦會放置一些顏色，看看病人會否有不正常的血流。此病人已經無任何血流橫跨封堵器附近，即代表如果病人將來不幸再有血塊出現，這些血塊也不會經過卵圓孔，由右心臟直接去左心臟。這些血塊只會由心臟經過肺部進行過濾。
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