A death certificate issued by The Los Angeles County Department of Public Health Monday night confirmed that actress Carrie Fisher died of cardiac arrest.
The document, first obtained by TMZ and later by the Associated Press, listed the cause of death as "cardiac arrest/deferred," indicating that more investigation by the county coroner is warranted. Usually, that means toxicology tests that can take several weeks to complete.
Fisher, 60, suffered a heart-related medical emergency shortly before her flight from London to Los Angeles was due to land on Dec. 23. Witnesses on the plane tweeted that she had stopped breathing for more than 10 minutes. She died four days later on Dec. 27 at Ronald Reagan UCLA Medical Center.
Photos: Carrie Fisher through the years
What is the difference between a heart attack and cardiac arrest?
Photos: Debbie Reynolds through the years
According to the American Heart Association, the quick and dirty explanation is that cardiac arrest is an electrical problem that causes the heart to stop pumping, whereas a heart attack is a circulatory problem caused when blood flow to a part of the heart is blocked due to arterial blockage or rupture.
"A heart attack is a sustained lack of blood supply to a particular part of the heart where the heart muscle starts to die," explains Dr. Jorge Plutzky, the director of preventive cardiology at Brigham and Women’s Hospital and Harvard Medical School.
He says that lack of blood supply can be due to blocked arteries, or often in the case of sudden heart attacks in patients with no prior symptoms, the rupture of plaque that has built up inside the arterial wall, and is prone to forming blood clots. "And now you've suddenly cut off blood supply."
While most heart attacks do not result in cardiac arrest, they can if the heart's normal rhythm is interrupted as a result.
"When someone's having a heart attack, the part of the heart that's not getting enough oxygen can go into a fatal arrhythmia (irregular rhythm) because the heart muscle cells that help conduct the electricity start dying," Plutzky says.
When that electrical malfunction occurs, the patient is in a state of cardiac arrest, meaning their heart has stopped effectively pumping blood to the brain, lungs and other organs. In that case, the American Heart Association says, the patient loses consciousness and has no pulse. Death can occur within minutes if the victim does not receive treatment.
Fisher was fortunate in that she went into cardiac arrest 15 minutes from LAX, where paramedics were standing by to provide advanced life support as soon as the plane landed.
"If Fisher dropped suddenly and passed out, then that wouldn't necessarily mean a heart attack, and in an autopsy, they can usually tell," Plutzky says. "They might have known when she got to the hospital whether she had one. As far as I know, they know she had cardiac arrest and now the question is what might have been the driver of that and that may be the more detailed analysis they're doing."
Debbie Reynolds died from hemorrhagic stroke
The cause of death for Fisher's 84-year-old mother, Debbie Reynolds, was more straightforward. The coroner did not perform an autopsy, citing Reynolds' recent history of small strokes.
According to her death certificate obtained by TMZ and AP, Reynolds died Dec. 28 at Cedars-Sinai Medical Center as a result of intracerebral hemorrhage, or a ruptured blood vessel that caused bleeding in her brain. According to the Cleveland Clinic, the condition is also referred to as a hemorrhagic stroke.
"Since the brain cannot store oxygen," the Cleveland Clinic site explains, "it relies upon a series of blood vessels to supply oxygen and nutrients. The pooling of blood from an intracranial hemorrhage or cerebral hemorrhage puts pressure on the brain and deprives it of oxygen. When a hemorrhage or stroke interrupts blood flow around or inside the brain, depriving it of oxygen for more than three or four minutes, the brain cells die."
Hypertension (high blood pressure) was listed as a contributing factor for Reynolds.
High blood pressure is also a risk factor for heart disease, Plutzky notes.
He says if one good thing has come out of the deaths of Fisher and Reynolds, "It's that more attention (is being paid to) the leading cause of death for women, which often gets overlooked ... You need to make sure people are thinking about it and doctors aren't dismissing it because you're a woman and you're not that old, so it can't be your heart. It has to be thought about."