The entertainment industry encountered major losses to serious heart-related events.
Both heart failure and cardiac arrest are confused with heart attacks and other conditions, though. Meanwhile, Thicke’s death was initially tied to a heart attack, too.
Here’s what you need to know about the three conditions.
What is heart failure?
Michael was only 53 when he died from heart failure.
WATCH BELOW: George Michael died of heart failure: manager
“It is with great sadness that we can confirm our beloved son, brother and friend George passed away peacefully at home over the Christmas period,” his publicist said in a statement.
Heart failure is a complicated and often misunderstood condition, but its rates are steadily rising as more people live with heart disease.
Doctors call heart failure a “revolving door” condition because it can be triggered by a gamut of issues: multiple heart attacks or heart disease could damage the organ, infections in the heart valve, dealing with high blood pressure, diabetes or genetics, electrical issues in pumping blood and even the aging process can lead to the onset of heart failure.
It’s when your heart’s shape and function is altered, making it difficult for it to adequately pump blood through your body.
Patients end up with fluid accumulating in their bodies, they can gain weight, they feel bloated and puffy, and their lungs get “wet” with their breathing laboured.
READ MORE: Pop music icon George Michael dead at 53
Ultimately, heart failure patients end up in hospital for extensive treatment for about one to two weeks for a “tune up.” But doctors can’t cure the problem, so patients are hospitalized again months later.
Depending on the symptoms, half of all heart failure patients die within five years of their diagnosis and most die within a decade.
What is cardiac arrest?
Petty was hospitalized on Sunday night after being discovered unconscious in full cardiac arrest. A statement from Tony Dimitriades said that Petty died at 8:40 p.m. PT, “surrounded by family, his bandmates and friends.”
In December, Fisher died after suffering full cardiac arrest while aboard an airplane headed to Los Angeles from London.
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Cardiac arrest is often confused with a heart attack. A heart attack is triggered when blood flow to the heart is blocked, while cardiac arrest occurs when the heart malfunctions and stops beating unexpectedly.
When it stops, it isn’t pumping blood to the brain, which is why paramedics have such a tight window to help patients before there’s a lasting impact on the brain.
The cardiac arrest, in most cases, becomes irreversible as seconds tick away.
Cardiac arrests are set off by arrthymia, or an irregular heartbeat, so bystanders need to provide chest compressions and run the AED to help revive patients.
What is a ruptured aorta?
Alan Thicke was playing ice hockey with his son Carter on Dec. 13 when he collapsed and later died.
WATCH BELOW: Actor Alan Thicke dead at 69
The 69-year-old Canadian actor’s death certificate said his aorta ruptured about three hours after it developed a tear. An aortic tear also killed actor John Ritter in 2003.
The aorta is the main artery that carries blood to your heart, brain, arms and the rest of your body. It’s shaped like a candy cane.
A dissection means there was a tear in the wall of the aorta and blood ends up in two channels instead of one. A Type A dissection means the rip occurred in the first part of the aorta, closest to the heart.
People with high blood pressure can tear their aorta if they have severe hypertension, while dissections can occur – in rare cases – from doing extremely strenuous weight lifting or from extreme emotional or physical exertion.
If people with a Type A dissection don’t get surgery, the risk of death increases by one per cent per hour.
Reports suggest Thicke made it to hospital and the emergency room but that he ultimately died while in the operating room.
Operating on a ruptured aorta can take up to eight hours. The patient is connected to a heart-lung machine, their body is cooled to reduce blood flow to the brain and the rest of the aorta is replaced with a graft and stitched back together. It’s an incredibly complicated procedure.
—With files from Chris Jancelewicz and Katie Scott