'Home Alone' actress Catherine O'Hara's cause of death revealed: She died of pulmonary embolism with cancer as the cause; how dangerous can the disease be?

Catherine O’Hara died from a pulmonary embolism, with cancer as the underlying cause. A Los Angeles County death certificate issued Monday lists the pulmonary embolism, which occurs when a blood clot blocks an artery in the lungs, as the immediate cause of the actor’s Jan. 30 death at age 71. Rectal cancer was the long-term cause.

The oncologist who signed off on the certificate indicated that he had been treating O’Hara since March of last year, and last saw her on Jan. 27. She died at a hospital in Santa Monica, California.

The beloved Canadian-born comic actor and “SCTV” alum starred as Macaulay Culkin’s mother in two “Home Alone” movies and won an Emmy as the dramatically oblivious wealthy matriarch Moira Rose in “Schitt’s Creek.”

Her death was a surprise to most, and an initial statement from her representatives said only that she died “following a brief illness.”

Collaborators including Culkin, Christopher Guest, Eugene Levy and Pedro Pascal paid her loving tribute after her death.

The document said she was cremated. It lists her profession as “actress” and her business as movies. It said she practiced her trade for 50 years.

What is pulmonary embolism and hoe dangerous can it be?

According to MedLine Plus, pulmonary embolism (PE) is a sudden blockage in a lung artery. It usually happens when a blood clot breaks loose and travels through the bloodstream to the lungs. PE is a serious condition that can cause: permanent damage to the lungs, low oxygen levels in your blood,
damage to other organs in your body from not getting enough oxygen.

(With inputs from The Associated Press)