Clinical InvestigationAcute Ischemic Heart DiseaseA multicenter comparison of established and emerging cardiac biomarkers for the diagnostic evaluation of chest pain in the emergency department
Section snippets
The IMAGINE Study
The IMAGINE study (Clinicaltrials.gov no. NCT00355992) was a multicenter, blinded prospective cohort study designed to evaluate subjects presenting to ED with symptoms suggestive of ACS, with primary goals of evaluating the diagnostic and prognostic use of IMA. With respect to the goal of evaluating the diagnostic value of IMA, the purpose was to validate the previously published negative predictive value (NPV) of the biomarker; for prognostic value, the goal was to explore the potential value
Study setting and population
Those consenting patients presenting with symptoms suggestive of a possible ACS meeting inclusion and exclusion criteria (Table I) were enrolled. Results of history, physical examination, chest x-ray, electrocardiogram (ECG), and laboratory assessments were recorded. Patients were followed up for 30 days from presentation; and all clinical information, including discharge diagnosis, was documented for the purpose of this study. The diagnosis of ACS was judged using standard criteria8; in brief,
Patient demographics and clinical factors:
Of the 318 patients enrolled in the study, 62 (19.5%) had a final diagnosis of ACS, of which 40 had UAP, according to standard criteria.8 Of the 62 patients with ACS, 43 had an abnormal angiography; 19, an abnormal stress test; and remaining few were adjucated the diagnosis on basis of clinical presentation. There were no cases of ST-segment elevation MI. Table II details clinical characteristics of study subjects as a function of diagnosis. Of note, very few patients demonstrated diagnostic
Discussion
The importance of biomarker testing for the diagnostic evaluation of the patient with suspected ACS is clearly established. Unfortunately, currently used biomarkers—such as cTnT—are time dependent for their detection; and at present, a reliable biomarker of coronary ischemia—that would detect all ACS, not just with myocardial necrosis—remains elusive. With this in mind, we compared, in rigorous statistical fashion, several biomarkers that are extensively discussed—but poorly validated—for
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Cited by (26)
Ischemia-modified albumin: Crosstalk between fatty acid and cobalt binding
2018, Prostaglandins Leukotrienes and Essential Fatty AcidsCitation Excerpt :The correlation between ACB assay readings and FFA levels is clear (Fig. 6b), provides a coherent explanation of the chemical identity of IMA, and is consistent with all clinical observations. Serum FFA, in particular unbound FFA, concentrations are useful biomarkers for early diagnosis of ACS [141]. We suggest that the ACB asay – or indeed one of its variants using other metal ions – may be re-purposed as a test for increased serum FFAs [22,25,140,142].
Circulating free fatty acids inhibit food intake in an oleate-specific manner in rats
2016, Physiology and BehaviorCitation Excerpt :In addition, we infused individual FFAs, dissolved in saline containing 0.5% albumin, to assess their effects on food intake. In all these experiments, we quantified major circulating FFA species for total [i.e., albumin bound + unbound] and unbound levels [27,28], and determined their relationships with feeding control. Male Wistar rats weighing 280–300 g (approximately 9 weeks old) were obtained from Simonsen (Gilroy, CA), unless stated otherwise, and studied at least 5 days after arrival.
Natriuretic peptides in heart failure and acute coronary syndrome
2014, Clinics in Laboratory MedicineUsefulness of serum unbound free fatty acid levels to predict death early in patients with st-segment elevation myocardial infarction (from the Thrombolysis in Myocardial Infarction [TIMI] II trial)
2014, American Journal of CardiologyCitation Excerpt :The determination of FFAu concentrations requires knowledge of the relative distribution of the different FFAu present in serum and was estimated from the distribution of total FFAs, as described in previous studies.6,13 Differences in the FFAu distributions, such as those that can occur in acute coronary syndromes,30 are not expected to significantly alter the total FFAu levels.6 The study was borderline underpowered for female patients, suggesting the need for additional studies.
Biomarkers after risk stratification in acute chest pain (from the BRIC Study)
2013, American Journal of CardiologyCitation Excerpt :This provides evidence that simply drawing a panel of admission biomarkers, including cardiac troponin, NT-proBNP, and cystatin C, after clinical risk stratification may allow more accurate discrimination between those patients needing further ischemia evaluation and those who can be discharged without the current guideline recommended stress testing within 24 to 72 hours of discharge.12 No previous study has associated biomarker results with the outcomes of stress tests, focusing instead on prognostic rather than diagnostic utility in high-risk populations. 13–17 We purposefully chose a pure clinical risk classification scheme that predated the use of troponin,8 favoring a mechanism for immediate-risk stratification on arrival to the ED.
Clinical trial registration: Clinicaltrials.gov no. NCT00355992.