A simple stumble on the stairs of her palatial Upper East Side apartment ended the life of Ivana Trump, the New York City medical examiner says.

The medical examiner’s brief report, released on Saturday, did not specify when the accident took place, but did appear to downgrade early suspicions that the 73-year-old suffered a fatal heart attack.

Her son, Eric Trump, said it was “a very sad day, a very sad day”.

“Ivana Trump was a survivor. She fled from communism and embraced this country. She taught her children about grit and toughness, compassion and determination,” the Trump family said in a statement earlier.

Ivanka Trump remembered her mother as “brilliant, charming, passionate and wickedly funny” on Friday, sharing a childhood photo of the pair together.

“She lived life to the fullest – never forgoing an opportunity to laugh and dance,” Ivanka said.

“I will miss her forever and will keep her memory alive in our hearts always.”

Tweet from @IvankaTrump

A Czech-born ski racer and businesswoman, Ivana Trump was born Ivana Zelnickova in 1949.

She was married to the former president from 1977 to 1992, and they had three children together: Donald Jr, Ivanka and Eric.

The Trumps became a 1980s power couple, and she managed one of his Atlantic City casinos as well as helped with the decor of Trump Tower.

Their marriage ended in a messy, public divorce after Donald Trump met his next wife, Marla Maples.

But in recent years, Ivana Trump had been on good terms with her ex-husband. She wrote in a 2017 book that they spoke about once a week.

Her death came during a fraught time for the Trump family.

Two of her children, Donald Jr and Ivanka, as well as the former president are due to appear for questioning a New York state civil investigation into the family’s business practices.

But the attorney-general’s office agreed to postpone the depositions because of Ivana Trump’s death.

-AAP