DALLAS, Feb. 16 -- Preliminary results of one of the nation's largest national surveys of Emergency Medical Services (EMS) systems indicate the need for improvements in the way heart attack, specifically ST-elevation myocardial infarction (STEMI), is managed.
STEMI is the most serious and deadly type of heart attack, characterized by a complete blockage of a coronary artery. It requires rapid response and treatment to reopen the artery and restore blood flow to the heart muscle. The preferred treatment is primary percutaneous coronary intervention (PCI), which involves mechanically opening the artery using a small balloon to clear the blockage followed by the insertion of a stent, a type of scaffolding used to prop open the artery.
The American Heart Association conducted the survey as part of its Mission: Lifeline initiative to improve the response and treatment of STEMI patients and ultimately all heart attack patients. The association gave the survey October - December 2008 to more than 5,400 EMS system or agency directors and asked questions about staffing, funding, training, and existing processes for handling patients who have experienced a STEMI.
The most significant findings:
- Only half of EMS systems have 12-lead electrocardiograms (ECGs), used to detect STEMI, on 75 percent or more of their vehicles.
- Of EMS systems with 12-lead ECGs:
- Most lacked a standard method for EMS to communicate the 12-Lead ECG results to the hospital. Currently, paramedics use one or more of the following methods: verbally reporting the ECG algorithm (an automatic, software-generated analysis of the ECG reading); verbally reporting their own interpretation of the ECG reading; or using an advanced technology like Blue Tooth or mobile phone to transmit the ECG algorithm or reading.
- EMS field personnel remotely activate hospital catheterization ("cath") labs only 40 percent of the time. (Cath labs perform procedures like angioplasty and stenting). This can significantly delay evaluation and treatment.
- Destination protocols are only used a third of the time to enable EMS to take STEMI patients directly to a hospital capable of providing angioplasty/stenting 24 hours a day, seven days a week. Instead, many EMS departments take patients to the closest hospital, which can cause significant delays to appropriate care.
- Only about 20 percent of hospitals are able to perform procedures like angioplasty and stenting for STEMI patients 24 hours a day, seven days a week.
"We were encouraged that more EMS systems than anticipated had vehicles equipped with 12 lead ECGs, devices that diagnose STEMI and other heart attacks," said Robert E. O'Connor, M.D., chair of the American Heart Association's Mission: Lifeline Emergency Cardiovascular Care task force. "However, we found the need for better systems to allow EMS to transmit data from ECGs and activate the cath lab on the way to the hospital and for policies allowing them to take patients to the facility able to provide appropriate care, whether it's the closest facility or not."
According to the American College of Cardiology/American Heart Association guidelines, primary PCI, typically balloon angioplasty with stenting, is the preferred treatment over clot busting drugs if it can be achieved within 90 minutes. EMS is a critical part of the system of care to decrease time to treatment for STEMI patients.
In coming months, the association's staff will receive survey data for their state or region and share it with coalitions composed of EMS and hospital personnel, physicians and nurses and health policy makers. The coalitions will use the information to create appropriate plans to improve the care of STEMI patients.