Sudden Cardiac Death Not So Sudden
People May Have Symptoms 2 Hours Before Cardiac Arrest
Sept. 8, 2006 -- Sudden cardiac death may not be so sudden after all.
A new study suggests people often develop symptoms of cardiac arrest, like
chest pain or breathlessness, around two hours beforehand. In addition, up to
two-thirds of sudden cardiac death victims have a history of heart disease that puts them at risk for cardiac
Researchers say learning to recognize these warning signs of cardiac arrest
may offer a window of opportunity to prevent sudden cardiac death.
"Our study suggests that shifting the focus to educating high-risk
patients and families may lead to earlier recognition, a quicker call to the
emergency medical system (EMS), a higher percentage of bystander CPR [cardio
pulmonary resuscitation], and thus to a higher probability of survival in
patients with sudden cardiac death," says researcher Dirk Muller, MD, PhD,
of the University of Berlin, in a news release.
Recognizing Cardiac Arrest
Cardiac arrest occurs when the heart abruptly stops pumping.
According to the American Heart Association, more than 330,000 people die
each year from heart disease before reaching a hospital, or in an emergency
room. Most of these deaths are caused by sudden cardiac arrest.
In the study, researchers examined 406 cases of cardiac arrest out of the
more than 5,000 rescue missions performed by doctors at a mobile intensive care
unit in Berlin.
The results showed 72% of the cardiac arrests occurred at home and 67% were
witnessed by a bystander.
Researchers collected information on symptoms preceding cardiac arrest on
323 of the 406 cases.
The most common warning symptom was chest pain lasting from 20 minutes to 10
hours and 30 minutes before the cardiac arrest, or a median of two hours. Chest
pain occurred in 25% of the cardiac arrests witnessed by others.
Breathlessness for 10 minutes was reported in 17% of witnessed cardiac
arrests; nausea or vomiting for 90 minutes before the arrest in 7%.
Other common symptoms were dizzinessor
Background history was available in 352 of the patients. Researchers found
that 106 of these cardiac arrest patients had a history of coronary artery
disease that put them at increased risk for cardiac arrest, and 16 had
experienced a previous cardiac arrest.
Quick Treatment Crucial
The study showed bystanders performed CPR on 57 patients, and 13 of those
patients (23%) survived to hospital discharge. Only 4% of cardiac arrest
patients who did not receive bystander CPR survived.
Researchers found CPR attempts occurred more often in public locations (26%)
than at home (11%).
They say the results suggest family members and caregivers of people with
heart disease and at increased risk should be trained to recognize symptoms and
perform CPR to reduce the likelihood of death from cardiac arrest.
"Training and prevention efforts should be focused on how to recognize
the emergency, CPR training, and automated external defibrillator (AED)
use," says Muller.