Princess Yuriko, the oldest member of Japan's imperial family and great-aunt of Emperor Naruhito, was released from hospital Thursday after receiving treatment for an abnormal heart rhythm, the Imperial Household Agency said.

The 97-year-old princess, the widow of Prince Mikasa, was admitted to St. Luke's International Hospital in Tokyo on Monday. Upon her release, she was displaying a healthy complexion and a good appetite, the agency said.

Undated photo shows Princess Yuriko, 97, the oldest member of Japan's imperial family and great-aunt of Emperor Naruhito. The Imperial Household Agency said on Sept. 28, 2020 that she has been diagnosed with heart failure in Tokyo but is in stable condition and able to converse. (Kyodo) ==Kyodo

The princess was initially expected to stay at the hospital for about a week, but was released sooner as her symptoms subsided shortly after her hospitalization and there were no signs of recurrence, the agency said.

She was taken to the hospital Monday when her heart rate registered higher than normal. The agency said the princess was admitted as a precautionary measure due to an existing heart condition.

The princess was hospitalized last fall for about two weeks for treatment of pneumonia and heart failure.

A member of Japan's former nobility, the princess married Prince Mikasa, younger brother of Emperor Hirohito, posthumously known as Emperor Showa, at the age of 18 in 1941. Her husband died of heart failure in 2016 at age 100.

The couple had three sons and two daughters. Their sons, princes Takamado, Tomohito and Katsura, died in 2002, 2012 and 2014, respectively.

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