Researchers have developed a simple laboratory score which is safer and faster at diagnosing patients who visit the emergency department with heart attack symptoms.

The findings, published in the CMAJ (Canadian Medical Association Journal), suggest that the score can also identify patients at risk of subsequent heart issues after discharge. "We have developed a simple lab score that is superior to using cardiac troponin alone for the identification of patients at low and high risk for heart attack or death at emergency department presentation," said co-author Peter Kavsak from the McMaster University in Ontario, Canada. 

"This lab score may reduce both the number of blood tests and the time spent in the emergency department for chest pain patients," Andrew Worster, Professor at the varsity, said. For the study, the team combined common laboratory blood tests available at several hospitals around the world to create a single laboratory score or clinical chemistry score, to diagnose a heart attack. 

These blood tests are part of the World Health Organization's (WHO) list of essential in vitro diagnostic tests for health care facilities with clinical laboratories. The researchers validated the clinical chemistry score as a predictor of heart attacks or deaths within 30 days, using the data on 4,245 patients from emergency department studies in four countries -- Canada, Australia, New Zealand, and Germany. 

Within one month of the emergency department visits, 727 heart attacks or deaths in patients occurred. A negative (or low-risk) clinical chemistry score at emergency department presentation missed only one of these events compared with up to 25 missed heart attacks or deaths when using a high-sensitivity cardiac troponin test alone. 

A positive (or high-risk) clinical chemistry score also identified about 75 per cent of the patients at high risk of heart attacks or deaths when positive compared with a low of 40 per cent detected when the high-sensitivity cardiac troponin test alone was positive. The researchers suggest the score can be useful for standardising diagnoses and improving safety.