Back to posts Your Stories: Meet Nanako

I am a Japanese female patient with Danon disease that has affected me and my twin sister in very different ways. While my sister has a confirmed diagnosis, she shows no symptoms and does not require treatment. On the other hand, I have developed atrial flutter, atrial fibrillation, and WPW syndrome.In February 2022, I was experiencing bradycardia symptoms and was hospitalized. During testing, a life-threatening arrhythmia was discovered, leading to the urgent decision to have an ICD implanted. Additionally, to stop arrhythmias like tachycardia and atrial flutter, I underwent ablation surgery three times over the next three years. My condition is now stable.

Nanako (right) and her twin sister (left)

I believe Danon disease is difficult to diagnose. I had an older brother who had liver problems at age 11 and heart issues at age 14. These were symptoms characteristic of Danon disease, but back then, we lived without knowing what illness it was. My mother found a research paper on Danon disease and eventually, my brother was diagnosed with Danon disease. My brother passed away at age 16, and I began experiencing symptoms when I was 14 and started on medications. My own diagnosis came after our persistence, despite initial reluctance from my regular doctor.

Living with Danon disease has meant facing not only physical challenges but also emotional ones. I am grateful for the care I receive despite the reality that there are very few Danon disease specialists in Japan. I hope that sharing my story contributes to research progress so that appropriate treatment reaches patients who need it as soon as possible.

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