Princess Yuriko is seen at the Toshimagaoka Cemetery in Tokyo after attending a memorial ceremony for her son Prince Tomohito of Mikasa on June 6, 2017, the fifth anniversary of his death. (Kyodo)

TOKYO - Princess Yuriko, the oldest member of Japan's imperial family and great-aunt of Emperor Naruhito, was discharged from hospital on Thursday after being diagnosed with heart failure and pneumonia, the Imperial Household Agency said.

Undated photo shows Princess Yuriko, 97, the oldest member of Japan's imperial family and great-aunt of Emperor Naruhito.(Kyodo) 

The 97-year-old princess, the widow of Prince Mikasa, was admitted to St. Luke's International Hospital on Sept. 24 after showing such symptoms as coughing and exhaustion.

She has a healthy complexion and an appetite, and will carry on her daily life as usual while making periodic visits to the hospital, the agency said.

The princess received medications as her heart's ability to pump blood had been weakening and pleural fluid was building up. Her condition remained stable during her stay in the Tokyo hospital, according to the agency.

She was fitted with a pacemaker in May 1999.

The princess is a member of Japan's former nobility. In 1941 at the age of 18, she married Prince Mikasa, younger brother of Emperor Hirohito, posthumously known as Emperor Showa. 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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