November 15, 2009
1 min read

Shortness of breath, chest pain most frequent prodromal symptoms preceding out-of-hospital cardiac arrest

Patients displaying prodromal symptoms tended to have more neurologically favorable outcomes at one month.

You've successfully added to your alerts. You will receive an email when new content is published.

Click Here to Manage Email Alerts

We were unable to process your request. Please try again later. If you continue to have this issue please contact

American Heart Association Scientific Sessions 2009

Patients suffering from cardiac arrest who displayed prodromal symptoms prior to arrest tended to get treated with emergency medical services earlier and have better outcomes than those not displaying the symptoms.

Researchers for the population-based cohort study analyzed more than 2 million individuals in Osaka, Japan between 2003 and 2004, and focused on 1,066 witnessed out-of-hospital cardiac arrest cases of presumed cardiac etiology in that population. Patients were included in the study if they were >18 years, had cardiac arrest witnessed by bystanders and were treated with emergency medical services.

Of the 1,066 patients who experienced observed out-of-hospital cardiac arrest, 651 had prodromal symptoms and 415 had no prodromal symptoms. Among the patients with prodromal symptoms, 389 (59.8%) showed symptoms in the minutes prior to cardiac arrest and 162 (24.9%) had symptoms an hour prior to cardiac arrest. The most frequent prodromal symptoms were shortness of breath (27.5%), followed by chest pain (20.6%) and syncope (12.9%). Patients who displayed prodromal symptoms were more likely to receive early CPR by EMS than those who did not have prodromal symptoms (P<.001). One-month survival was greater in prodromal symptoms than those with no prodromal symptoms (12.1% vs. 7.7%, P=.023). Ventricular fibrillation as initial rhythm (OR=3.9; 95% CI, 1.8-8.3), arrest after EMS arrival (OR=20.8; 95% CI, 1.5-280.7) and earlier call to EMS (OR per minute=0.78; 95% CI, 0.66-0.92) were all associated with better neurological outcomes.

“While 60% of patients experienced symptoms within a few minutes of arrest, the remaining 40% have symptoms within an hour,” said Chika Nishiyama, of the Kyoto University School of Public Health, said in a press conference. “Noticing such prodromal symptoms would facilitate early activation of EMS and may prevent sudden cardiac death.” - by Eric Raible

For more information:

  • Nishiyama C. Abstract 2702. Presented at: American Heart Association Scientific Sessions 2009; Nov. 14-18; Orlando, Fla.