Missed diagnoses of STEMI eliminated in regional Australian trial

A trial of a decision support service for rural hospitals without emergency medicine specialists has reduced the proportion of missed STEMI diagnoses to zero and increased the rate of reperfusion therapy.

The Management of Rural Acute Coronary Syndromes (MORACS) trial randomised 29 rural hospitals in the Hunter New England Local Health District to either usual care or the MORACS decision-support intervention.

In the intervention group, a MORACS nurse at a central hub in the LHD was notified via automated text of any patients with ACS symptoms. The nurse remotely reviewed ECG and troponins via the electronic medical record then contacted the rural hospital to advise and document pathway-guided care.

The study, published in JAMA Cardiology, said clinicians at rural hospitals could also contact the MORACS team directly by phone to review patients in the ED with suspected ACS.

Over the study period from December 2018 to April 2020, STEMI was the final diagnosis in 77 patients (2.0%) in the usual care hospitals and 46 (1.3%) in the MORACS hospitals.

The primary outcome of missed STEMI, defined as failure to recognise STEMI on the ECG and initiate treatment for STEMI according to Australian guidelines, occurred in 35% of patients in usual care hospitals and 0% in MORACS hospitals (P < 0.001).

“Of those eligible for primary reperfusion, 48 of 75 patients (64%) in the usual care group and 36 of 36 (100%) in the MORACS group received reperfusion therapy (P<0.001),” the study said.

There were no statistically significant differences in reperfusion time, length of stay, or 30-day readmission rates.

Mortality at 12 months was 6.5% (n = 3 of 46) in the MORACS intervention group vs 10.3% (n = 8 of 77) in the usual care group (relative risk: 0.64, 95% CI: 0.18–2.23, P = 0.48).

“Findings demonstrate that a centralised diagnostic support service significantly reduced the proportion of missed STEMI. Accurate diagnosis of STEMI resulted in higher rates of initiating primary reperfusion. Further, a correct STEMI diagnosis was associated with lower mortality.”

Unexpected success

The study, led by the LHD’s cardiac liaison officer and nurse Ms Fiona Dee said the intervention improved the accuracy of ECG interpretation to an “unexpected” level of success, despite the fact that all ECG machines in the district had automated algorithms to assess for STEMI.

“This model for supporting diagnosis and management of ACS may be easily adapted and scaled across a variety of healthcare environments,” it said.

An Invited Commentary in the journal said the Australian study had international implications, including in the US which had a similar population distribution, growing urban-rural inequalities, and workforce shortages in rural communities.

“The study demonstrates that a centralised diagnostic support service can significantly reduce the proportion of missed STEMI.”

“Further, accurate STEMI diagnosis resulted in higher rates of initiation of primary reperfusion and was associated with lower mortality.”

The US authors said that while the technologies and resources used in the study to improve STEMI diagnosis were widely available and easily adaptable, the policy barriers may be harder to overcome.

“Clinical leaders and professional societies could advocate for hospital initiatives to reduce rural-urban health disparities to receive designation as a STEMI centre of excellence, which would create additional incentives to create rural-urban hospital connections and partnerships.”

Already a member?

Login to keep reading.

Email me a login link

© 2022 the limbic