Guidelines for the assessment of chest pain in Australian emergency departments need to be reassessed according to the authors of research published in the Medical Journal of Australia.
A team of researchers from Royal Brisbane and Women's Hospital (RBWH), Queensland University of Technology, Christchurch Hospital and the University of Queensland, found that of 926 patients presenting to emergency departments with chest pain between November 2008 and February 2011, 11.1% (103) were diagnosed with an ACS, while 20.8% were diagnosed with other cardiovascular-related conditions, and 67.2% had non-cardiac-related chest pain.
Led by Associate Professor Louise Cullen, an emergency physician and Professor Will Parsonage, a cardiologist at RBWH, the authors wrote that the study was "the first evaluation of the characteristics, final diagnoses, outcomes and costs for an Australian emergency department (ED) cohort investigated for possible ACS based on the National Heart Foundation and Cardiac Society of Australia and New Zealand (NHF/CSANZ) guidelines". Those guidelines recommend stratifying patients who present with chest pain into low-, intermediate- and high-risk categories.
Low-risk patients are assessed using serial cardiac biomarkers and electrocardiography. High-risk patients require admission to hospital and intensive management, often including early invasive strategies. The largest group is the intermediate-risk cohort, who require serial testing of biomarkers and electrocardiography. If results of these are negative, the authors wrote, further objective testing is required, the most common of which in Australia is an exercise stress test (EST).
"ACS events occurred in 0 and 11 (1.9%) of the low-risk and intermediate-risk groups, respectively", the authors wrote of their study participants.
"Ninety-two (28.0%) of the 329 high-risk patients had an ACS event."
"Patients with an ACS, high-grade atrioventricular block, pulmonary embolism and other respiratory conditions had the longest length of stay."
"The mean cost was highest in the ACS group ($13 509) followed by other cardiovascular conditions ($7283) and non-cardiovascular conditions ($3331)."
Overall, in terms of costs, the study found that the total ED cost for investigating the 926 patients was $904 221, while inpatient costs totalled $3 977 234. Total ED length of stay (LOS) was 5575.9 hours, making the average cost per hour in ED $162. Total LOS as an inpatient was 59 061.9 hours, making the average inpatient cost $67 per hour.
"Most ED patients with symptoms of possible ACS do not have a cardiac cause for their presentation", the authors concluded.
"The current guideline-based process of assessment of this cohort is lengthy and requires significant resources." "Further research efforts should be directed to identifying patients who could be discharged without requiring additional cardiac investigations."
"Investigation of strategies to shorten this process or safely reduce the need for objective cardiac testing in patients at intermediate risk according to the NHF/CSANZ guidelines is required."