APACE results lean toward troponin testing alone -- except when unstable angina is in the mix
Adding clinical judgment and ECG findings to high-sensitivity cardiac troponin (hs-cTn) assay doesn't always improve rule-out for patients presenting with suspected acute MI in the emergency department, researchers found.
The hs-cTnT 0/1 h algorithm from the European Society of Cardiology (ESC) used by itself was actually able to safely rule out more events in the APACE study, according to Christian Mueller, MD, of University Hospital Basel, Switzerland, and collaborators.
Use of the three pillars of triage together left 45% of patients ruled unlikely to have major adverse cardiac events (MACE) within 30 days, compared with 60% ruled out by the assay alone (P<0.001), the researchers reported in the Aug. 20 issue of the Journal of the American College of Cardiology.
Actual 30-day MACE rates were similar after triage by either algorithm (0.4% vs 0.6%, P=0.429), yielding similar negative predictive values (99.6% vs 99.4%, P=0.097).
The ESC hs-cTnT 0/1 h algorithm by itself ruled in fewer patients (16% vs 26%, P<0.001) with a higher positive predictive value (76.6% vs 59%, P<0.001) compared with the extended algorithm.
MACE was defined as all-cause death, cardiac arrest, acute MI, cardiogenic shock, sustained ventricular arrhythmia, and high-grade atrioventricular block within 30 days.
When unstable angina leading to early revascularization was added into the mix, the ESC hs-cTnT 0/1 h algorithm retained a higher positive predictive value for rule-in, whereas the extended algorithm had higher negative predictive value for rule-out.
Thus, the assay used alone "better balanced efficacy and safety" in predicting MACE, whereas the addition of clinical assessment and ECG results should be the preferred option for ruling out 30-day MACE and unstable angina, Mueller's group concluded.
"It is important to highlight that the MACE rate ... in the rule-out group of the ESC hs-cTnT 0/1 h algorithm only was 0.6%, and therefore within the range requested by ED [emergency department] physicians in a survey for patients considered for discharge from the ED," the authors noted.
Their analysis of APACE included 3,123 patients presenting within 12 hours of acute chest discomfort onset at 12 centers in Europe in 2006-2015.
Similar study findings were observed with hs-cTnI.
The study reinforced the accuracy of hs-cTn 0/1 h algorithms to predict AMI and 30-day acute MI-related events, but a thorough assessment of patient's history and ECG findings continues to be essential, concluded an accompanying editorial, pointing in particular to the MACE plus unstable angina (UA) results.
"Although the prevalence and prognostic implications of UA have been changed by using hs-cTn to the point that it has been suggested removing it from the ACS [acute coronary syndrome] spectrum, the diagnosis of UA is still commonly used and continues to be associated with an increased risk in the era of hs-cTn," Germán Cediel, MD, PhD, of Hospital Universitari Germans Trias i Pujol in Barcelona, and colleagues wrote.
Another concern is the usefulness of the 0/1 h algorithm in those presenting within 2 hours of symptom onset, although the negative predictive value of both algorithms was more than 99%, they added.
Moreover, the APACE investigators acknowledged that some patients were excluded because they did not have a 1-hour troponin reading. Those with end-stage renal failure or equivocal final diagnoses were also excluded.
The study was supported by research grants from the Swiss National Science Foundation, the Swiss Heart Foundation, the European Union, the Cardiovascular Research Foundation Basel, the University Hospital Basel, Abbott, Beckman Coulter, BioMerieux, BRAHMS, Roche, Nanosphere, Siemens, Ortho Diagnostics, and Singulex.
The hs-cTn assays were donated by the manufacturers.
Mueller disclosed research support from the Swiss National Science Foundation, the Swiss Heart Foundation, KTI, the European Union, the University of Basel, the University Hospital Basel, the Stiftung für kardiovaskuläre Forschung Basel, Abbott, Beckman Coulter, BioMerieux, Idorsia, Ortho Clinical Diagnostics, Quidel, Roche, Siemens, Singulex, and Sphingotec. Mueller also has received speaker or consulting honoraria from Abbott, Amgen, AstraZeneca, BioMerieux, Boehringer Ingelheim, Bristol-Myers Squibb, Brahms, Cardiorentis, Idorsia, Novartis, Roche, Sanofi, Siemens, and Singulex.
Cediel disclosed no conflicts.
Journal of the American College of Cardiology
Source Reference: Nestelberger T, et al "Predicting major adverse events in patients with acute myocardial infarction" J Am Coll Cardiol 2019; DOI: 10.1016/j.jacc.2019.06.025.
Journal of the American College of Cardiology
Source Reference: Cediel G, et al "Ruling out acute coronary syndromes: troponin is essential, as is clinical assessment" J Am Coll Cardiol 2019; DOI: 10.1016/j.jacc.2019.05.065.
Read the original article on Medpage Today: Can hs-cTn Go It Alone in Acute MI Triage?