Can you literally be scared to death? Science says yes

Can people literally be scared to death? It sounds like the stuff of ghost stories and B movies, but physicians say the phenomenon is rare but real—and shows how fear from the brain can affect the heart, specifically with a rush of adrenaline.

Doctors around the world are increasingly identifying an unusual heart problem even in otherwise healthy people who have suffered a severe fright, a traumatic experience or loss of a loved one.

"You have people in acute, sudden heart failure who were perfectly healthy an hour earlier," says Ilan Wittstein, a cardiologist at Johns Hopkins Hospital in Baltimore who has studied the phenomenon, known as stress cardiomyopathy.

While many of these patients survive, others don't. Martin A. Samuels, chairman of the neurology department at Brigham and Women's Hospital in Boston, has collected hundreds of reports of people who have died suddenly in frightening situations. These include victims of muggings and break-ins whose assailants never touched them; children who died on amusement-park rides; car-accident victims who sustained only minor injuries and a man who jumped off the roof of Brigham and Women's Hospital in 1980 but suffered severe heart damage before hitting the ground.

Studies have also documented an increase in sudden deaths in the vicinity of the 1991 Iraqi missile attacks on Tel Aviv; the 1994 earthquake in Northridge, Calif., and the Sept. 11, 2001 terror attacks on Washington, D.C., and New York City.

"The unifying factor is that the nervous system controls the heart and it can do a lot of damage," says Dr. Samuels.

He and other experts believe that many of these deaths are due to a sudden heart malfunction set off by a surge of stress hormones from the body's fight-or-flight system. When the brain perceives a threat, this primitive response activates the sympathetic nervous system, which sends adrenaline and other chemicals called catecholamines to increase a person's heart rate and blood pressure, tense muscles, constrict blood vessels and prepare the body for action.

Much of the time, the body takes the adrenaline rush in stride—"after all, it helped humans survive in the wild," Dr. Samuels says. But an exaggerated stress response can damage the cardiovascular system in several ways.

Fear can cause a classic heart attack in people who are already at risk. "A person who is walking around with a 50% narrowing of the arteries may never have symptoms, but if they're held up at gunpoint or narrowly miss an auto accident, their adrenaline levels can rise and destabilize that plaque," says Dr. Wittstein. "That ruptured plaque can cause a blood clot to form and now they have a 100% blockage."

An adrenaline surge can also disrupt the heart's normal rhythm, causing ventricular fibrillation, in which the heart beats wildly and ineffectively. Ventricular fibrillation is thought to cause about 75% of the 325,000 cases of sudden cardiac death, when the heart ceases to beat, in the U.S. a year.

It isn't known how many sudden cardiac deaths might be fear-related because many victims don't undergo autopsies. Even if they did, the evidence of stress is elusive.

One indication: A study of 200 New York patients with implanted defibrillators (which fire automatically when a rhythm disruption occurs) found that twice as many had recorded life-threatening arrhythmias in the 30 days after the Sept. 11 terror attacks as in the 30 days before. "If they hadn't had those defibrillators, a lot of those people would be dead," Dr. Wittstein says.

Stress cardiomyopathy, the fear-related heart problem that affects healthy people, was first described by Japanese physicians in 1990 and dubbed "takotsubo syndrome," after Japanese octopus traps, because patients' hearts took on the same odd shape, ballooning in one area and contracting in another.

Dr. Wittstein described 19 cases of stress cardiomyopathy in an article in the New England Journal of Medicine in 2005, and since then, it has been diagnosed in thousands of patients around the world and written about in hundreds of journal articles.

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