Calling an ambulance improves heart attack survival

The Acute Cardiac Care Congress 2012 is the first annual meeting of the newly launched Acute Cardiovascular Care Association (ACCA) of the European Society of Cardiology (ESC). It takes place from 20 to 22 October in Istanbul, Turkey, at the Istanbul Lufti Kirdar Convention and Exhibition Centre (ICEC).

Primary percutaneous coronary intervention (pPCI), also called balloon treatment, opens the coronary vessel and is preferred over intravenous (IV) medicine (called thrombolysis) to dissolve blood clots in patients with heart attacks. To deliver this care, patients must be transported to a hospital that can provide balloon treatment. This requires well functioning treatment networks which integrate the pre-hospital and in-hospital phases of patient management so that even patients in remote areas receive high quality treatment that adheres to ESC Clinical Practice Guidelines.

"Transporting patients to hospitals with balloon treatment capacity often involves bypassing local hospitals in the vicinity of the patient," said Dr Mikkel M. Schoos from the University Hospital of Copenhagen, Denmark. "Pre-hospital triage involves digital transmission of the ambulance electrocardiogram (ECG) using telemedicine to the attending cardiologist at the hospital with the balloon capacity who can decide if the patient needs balloon treatment."

He added: "In this way, patients can be referred directly to the hospital that can perform balloon treatment, without first being seen in a local emergency room. This saves important time. We know from previous studies that reduced time to treatment equals greater salvage of the heart tissue near the blood clot after a heart attack."

Dr Schoos' study investigated the quality of these treatment networks in Denmark. The researchers found that 75% of all patients can be transferred directly to hospitals with balloon treatment capacity using pre-hospital triage.

But even when well functioning pre-hospital triage with telemedicine is in place, for 25% of patients it is not possible to deliver treatment within the time targets recommended by ESC Clinical Practice Guidelines if only ground ambulance is used. These are patients who live more than 100km (60 miles) away from the hospital with balloon treatment facilities and patients who go to a local hospital first.

The study showed that patients who are first brought to a local hospital lose important time and this increases their risk of death. "The time delay caused by first being taken to a local hospital that does not have the treatment facilities the patient needs is bad for the patient," said Dr Schoos. "Our study also shows that this system delay predicts all cause mortality in these patients who have big heart attacks. That means that a pit stop at a local hospital increases the risk of death."

There are several reasons why patients might go to the local hospital first. One is that the heart attack is not developed enough to be detected and diagnosed by the ambulance ECG. Dr Schoos is currently investigating ways to improve early diagnosis with ECG or biomarkers in the blood. A second reason could be a failure to transmit the ambulance ECG to the hospital. A third reason is that emergency medical personnel are not confident that the patient is stable enough for further transport and decide to do a pit stop at a local hospital.