Boston, MA - Only one in four patients transported to the hospital by emergency medical services (EMS) is receiving a prehospital electrocardiogram (ECG), a new study has shown [1]. Those who are screened with an ECG, however, are reperfused faster and more frequently than those who do not receive a prehospital ECG with first medical contact, report investigators.

"We hope the findings drive home the message that irrespective of reperfusion strategy, whether in an academic center that can do primary PCI 24/7 or a community hospital that utilizes fibrinolysis, an EMS system that transports patients who have chest pain and performs an ECG before arriving at the hospital improves our patients' outcomes and improves time to reperfusion," lead investigator Dr Deborah Diercks (University of California Davis Medical Center, Sacramento) told heartwire.

The study is published in the January 13, 2009 issue of the Journal of the American College of Cardiology.

In August 2008, the American Heart Association (AHA) issued a scientific statement on the use of prehospital ECGs to improve the quality of care delivered to STEMI patients. The AHA guidelines, as well as other consensus and scientific statements, recommend the acquisition and use of prehospital ECGs by EMS for the evaluation of patients with suspected acute coronary syndrome. The current recommendation is class 2a with a B level of evidence.

In this recent study, Diercks and colleagues evaluated patients with STEMI in the National Cardiovascular Data Registry (NCDR) Acute Coronary Treatment and Intervention Outcomes Network (ACTION) over a one-year period in 2007.

In total, 7098 patients utilized the EMS, and of these patients, just 27.4% received a prehospital ECG. Within this EMS transport population, 92% of those who received a prehospital ECG underwent primary PCI compared with 86% of those who received an ECG in the hospital. Also, more patients receiving an ECG in the ambulance were treated with fibrinolytic therapy compared with those who received one in the hospital.

Reperfusion times among STEMI patients screened with an ECG by EMS personnel were also shorter compared with those who received an ECG in the hospital. Similarly, more patients who received a prehospital ECG met the AHA door-to-balloon time recommendations of less than 90 minutes for PCI and the door-to-needle time of less than 30 minutes for fibrinolysis.

"I think what really improves the quality of care with the prehospital ECG is the time it takes to activate the system," said Diercks. "The prehospital ECG allows institutions to open up the lab, get their personnel ready, so that when the patient arrives the machine is started—the patient can get to where they need to go in a more prompt fashion."

Just one in four patients receiving an ECG prior to arriving at the hospital is a surprising finding, said Diercks. She added, however, that this study comes on the heels of the latest recommendations for prehospital ECG screening, so there might be insufficient time to see changes in the system. Increasing funding, training for EMS personnel to develop skills to interpret the ECG, and improvements in data transmission will hopefully result in an increase in utilization, she said.

In addition to improvements in reperfusion, investigators observed a trend toward improved clinical outcomes among patients who received a prehospital ECG. There were trends toward lower mortality, less congestive heart failure, and less cardiogenic shock among STEMI patients screened with an ECG by the EMS personnel. Although it failed to reach statistical significance, the risk of death was reduced 20% among those who received an ECG with first medical contact.

"The findings fall in line with what we know," said Diercks. "The faster we're able to reperfuse these people, the better their outcomes are. A reduction in mortality is very much in line with the reduced time to reperfusion with the prehospital ECG."