Catherine O'Hara died from a pulmonary embolism, according to the actress's death certificate, which was obtained by USA TODAY on Feb. 9. TMZ was first to report the news.
A pulmonary embolism is a blood clot that blocks blood flow to an artery in the lung, according to the Mayo Clinic.
Cast member Catherine O'Hara poses on the red carpet during arrivals for the screening of the film "Beetlejuice Beetlejuice" out of competition, during the 81st Venice Film Festival, Venice, Italy, Aug. 28, 2024.
This is considered a medical emergency as it causes issues with blood flow and oxygen levels in your lungs, the Cleveland Clinic adds.
According to reports, O'Hara, 71, died within hours of the onset of symptoms, the document reads. She was also diagnosed with rectal cancer, according to the death certificate.
Here's what to know about the health complication.
Pulmonary embolism symptoms
A pulmonary embolism is one of the most common heart and blood vessel conditions in the world, according to the Cleveland Clinic, with about 900,000 people a year in the United States experiencing one.
Though symptoms can vary based on clot size and underlying conditions, the Mayo Clinic says common signs include shortness of breath, chest pain and fainting.
Other symptoms may include:
- Cough with bloody mucus
- Rapid or irregular heartbeat
- Lightheadedness or dizziness
- Excessive sweating
- Fever
- Leg pain or swelling, or both, usually in the back of the lower leg
- Clammy or discolored skin
What causes a pulmonary embolism?
A pulmonary embolism occurs when "a clump of material, most often a blood clot, gets stuck in an artery in the lungs, blocking the flow of blood," according to the Mayo Clinic. And in many cases, multiple clots are involved.
Blood clots most commonly come from the deep veins of your legs, a condition known as deep vein thrombosis, the clinic notes.
Sometimes blockages in the blood vessels are caused by other substances such as fat from broken bones, part of a tumor or air bubbles, the clinic added.
"Without quick treatment, a pulmonary embolism can cause heart or lung damage and even death," the Cleveland Clinic notes. "About 33% of people with a pulmonary embolism die before they get a diagnosis and treatment."
Who is at risk for a pulmonary embolism?
Anyone can develop clots that lead to a pulmonary embolism, the Mayo Clinic says, but certain factors can increase your risk.
Those factors include a history of blood clots; medical conditions like heart disease, certain cancers, surgery, clotting disorders and COVID-19. Extended periods of inactivity, including bed rest and long trips, can also increase your risk.
Other factors are smoking, being overweight, supplemental estrogen and pregnancy.
Pulmonary embolism prevention and treatment
To help prevent a blood clot from forming, people should be physically active, use compression devices or leg elevation when needed. Those at risk of clots should take blood thinners.
Medical professionals use blood tests and other scans to diagnose a pulmonary embolism, the clinic adds, and can treat them in a number of ways depending on the severity, including said blood thinners or other therapies and procedures.
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