This additional stress on recovering patients is under-diagnosed, researchers say, and doctors have few standard methods for identifying who is at risk.

"Anxiety, depression and PTSD are major concerns after cardiac arrest," said lead author Kathryn Wilder Schaaf, a postdoctoral fellow at Virginia Commonwealth University. "We have the tools to treat this, (so) it's important to make sure that it's identified," she added.

Many long-term care issues for survivors are unknown, experts said, largely because only 10 percent of the 382,800 Americans who suffer cardiac arrest each year survive.

And that rate is higher than in the past. Cardiac arrest - when the heart stops beating suddenly and completely - is distinct from conditions often labeled as "heart attacks." In cardiac arrest, if the heart is not re-started quickly, brain damage or death usually results.

Cold therapy, which can protect the brain for a time, and implanted defibrillator devices, which can re-start an arrested heart, have helped to lower the death toll from cardiac arrest, but little is known about what mental and emotional scars may linger among survivors.

Wilder Schaaf and colleagues reviewed 11 studies published between 1993 and 2011 that looked at mental health issues following cardiac arrests experienced outside of a hospital and found problems plaguing anywhere from 15 percent to 50 percent or more of patients.

Months to years after surviving cardiac arrest, about one-third of patients were depressed and nearly two-thirds were experiencing anxiety. Even PTSD symptoms were surprisingly common, afflicting 19 percent to 27 percent of survivors, the medical literature showed.

In reality, however, the long-term mental health state of many cardiac arrest survivors is not typically considered or assessed, the researchers write in their report, which appears in the journal Resuscitation.

But treating mental illnesses in other types of heart patients has been shown to increase long-term survival while decreasing costs, according to independent research.

In a study published in November, for example, researchers found that a depressed patient recovering from a heart attack treated with psychotherapy and antidepressants during a six-month trial incurred - on average - $1,857 in medical costs, whereas a depressed patient who received no psychological treatments cost an average of $2,797 over the same time period.

Other research suggests that mental health issues impact physical recovery, too. Over a five-year period, survivors of cardiac arrest and similar events who did not show signs of PTSD lived three and a half times longer than those with ongoing trauma, according to a 2008 study by Dr. Karl-Heinz Ladwig, an epidemiologist at the Helmholtz Zentrum München in Germany.

Stress can affect the nervous system and impact heart rates, as well as worsening chronic inflammation, which also hurts the heart Ladwig told Reuters Health.

"We have problems convincing cardiologists to understand that depression is a very relevant part of their clinical work," Ladwig said.

Ladwig suggested that doctors can gauge trauma through screening questions that are, "easy to put in a normal discussion."

"This is a brand new area that is going to require thoughtful scientists, vigilant family members and an awareness from patients," said Dr. Karina Davidson, director of the Center for Behavioral Cardiovascular Health at Columbia University Medical Center in New York, who was not involved in the new study.

Nightmares plus an avoidance of doctors, medications or follow-up appointments are all signs that a recovering heart patient should seek mental health help, Davidson said.

Psychological recovery includes the patient developing feelings of safety and believing the future will be prosperous, said Samuel Sears, a professor at East Carolina University who studies the psychological effects of cardiac trauma.

A range of tools can help patients achieve that goal, including peer support groups such as the Sudden Cardiac Arrest Survivors Association and smart-phone apps such as ICD Coach (in which Sears has a financial interest), he noted.

Sears said he is optimistic that an understanding of the connection between head and heart will eventually reach the doctor's office.

SOURCE: bit.ly/TUsLLI Resuscitation, online December 3, 2012.

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