A large Asian/Australasian study examined a 2hr triple-marker test in patients presenting with chest pain.
BACKGROUND: Patients with chest pain contribute substantially to emergency department attendances, lengthy hospital stay, and inpatient admissions. A reliable, reproducible, and fast process to identify patients presenting with chest pain who have a low short-term risk of a major adverse cardiac event is needed to facilitate early discharge. We aimed to prospectively validate the safety of a predefined 2-h accelerated diagnostic protocol (ADP) to assess patients presenting to the emergency department with chest pain symptoms suggestive of acute coronary syndrome.
METHODS: This observational study was undertaken in 14 emergency departments in nine countries in the Asia-Pacific region, in patients aged 18 years and older with at least 5 min of chest pain. The ADP included use of a structured pre-test probability scoring method (Thrombolysis in Myocardial Infarction [TIMI] score), electrocardiograph, and point-of-care biomarker panel of troponin, creatine kinase MB, and myoglobin. The primary endpoint was major adverse cardiac events within 30 days after initial presentation (including initial hospital attendance). This trial is registered with the Australia-New Zealand Clinical Trials Registry, number ACTRN12609000283279.
FINDINGS: 3582 consecutive patients were recruited and completed 30-day follow-up. 421 (11.8%) patients had a major adverse cardiac event. The ADP classified 352 (9.8%) patients as low risk and potentially suitable for early discharge. A major adverse cardiac event occurred in three (0.9%) of these patients, giving the ADP a sensitivity of 99.3% (95% CI 97.9-99.8), a negative predictive value of 99.1% (97.3-99.8), and a specificity of 11.0% (10.0-12.2).
INTERPRETATION: This novel ADP identifies patients at very low risk of a short-term major adverse cardiac event who might be suitable for early discharge. Such an approach could be used to decrease the overall observation periods and admissions for chest pain. The components needed for the implementation of this strategy are widely available. The ADP has the potential to affect health-service delivery worldwide.
A 2-h diagnostic protocol to assess patients with chest pain symptoms in the Asia-Pacific region (ASPECT): a prospective observational validation study.
Lancet. 2011 Mar 26;377(9771):1077-84
Full text link available at time of writing
In an accompanying editorial, nicely entitled ‘Acute MI: triple-markers resurrected or Bayesian dice?’ Dr Rick Body notes that the point-of-care triple-marker test has a relatively low sensitivity, at just 82.9%, when used alone, and the sensitivity only increased to 99.3% in the current study because it was used in an already-selected low-risk population. He writes: “Most people will probably consider this net risk to be statistically acceptable. However, if properly informed, low-risk patients might feel differently about the relative merits of waiting for definitive six-hour laboratory-based troponin testing or going home after two hours on the basis of results from a test that correctly identifies serious coronary disease, when present, in just over eight of 10 occasions.”
Dr Body has a new blog at The Bodsblog where we’re likely to be informed other data relevant to emergency cardiology as they emerge.
Point-of-care panel assessment using a similar triple-marker test at presentation and 90 minutes was also examined in the RATPAC study, in which it increased successful discharge home and reduced median length of stay, but did not alter overall hospital bed use.