The Access AccuTnI+3 troponin I blood test is a paramagnetic particle, chemiluminescent immunoassay for the quantitative determination of cardiac troponin I (cTnI) levels in human serum and plasma using the Access 2 Immunoassay System or UniCel DxI Access Immunoassay System to aid in the diagnosis of myocardial infarction. The precise magnitude of change in the post-market cardiac troponin study data were not evaluated by FDA as part of the product’s 510(k) clearance.
New Study in Clinical Biochemistry Journal Identifies the Precise Magnitude of Change in Cardiac Troponin Required for Early Diagnosis of Heart Attack
Current clinical guidelines for MI diagnosis require demonstration of a rise and/or fall in troponin values (a protein released from damaged heart cells and detected in the blood) between samples collected in sequence following presentation to the Emergency Department. However, the guidelines do not quantify what a clinically significant rise and/or fall is—referred to as "delta" in literature. Without a defined delta, physicians do not have a consistent approach for diagnosing MI.
For the past several years, a majority of publications have suggested a percentage-change in troponin levels as the appropriate change criteria for determining if a patient has had a heart attack. However, this method has proven to not be fully reliable and more recent publications suggest that absolute values may perform better. The results of this new study recommend movement away from a percentage-change reading and rather to using an absolute difference by ng/mL change.
The study, which consisted of nearly 2,000 patients enrolled at 14 institutions, reports representative diagnostic performance that would be observed in clinical practice for early rule-in and rule-out of heart attacks, and demonstrated that absolute changes (0.01 or 0.02 ng/mL) performed significantly better than relative (percentage) changes at all time intervals after Emergency Department admission."Study results suggest that the majority of patients with myocardial infarction can be identified at earlier observation times, and support consensus recommendations for an optimal blood sampling protocol with troponin measurement on admission and three hours later," said principal investigator and lead author Alan B. Storrow, MD, vice chairman for Research and Academic Affairs, Department of Emergency Medicine, Vanderbilt University. "Another key finding of the study is that rule-out (correct identification of patients without a heart attack) was nearly 100 percent when baseline troponin was less than the diagnostic threshold of 0.03 ng/mL and absolute delta troponin was less than 0.01 ng/mL."
New Study in Clinical Biochemistry Journal Defines the Precise Magnitude of Change in Cardiac Troponin Required for Early Diagnosis of Heart Attack
"As troponin values rose, the probability of myocardial infarction increased. Baseline troponin values greater than 0.20 ng/mL were associated with nearly 90 percent probability of myocardial infarction. Earlier rule-in and rule-out may potentially save patient lives," said Paula Southwick, PhD, co-author and principal clinical research scientist at Beckman Coulter Diagnostics.
The results of this robust, clinical study were published as two companion articles in a special cardiac biomarkers issue of Clinical Biochemistry.1, 2
About Beckman Coulter
Beckman Coulter Diagnostics develops clinical diagnostic products that help advance and optimize the clinical laboratory. Beckman Coulter's instruments, systems and tests help streamline processes to enhance efficiency, reduce costs and speed the delivery of results. For 80 years, Beckman Coulter has been a global leader devoted to providing solutions to laboratories of all sizes, offering a broad portfolio of chemistry, immunoassay, hematology, urinalysis, microbiology, automation and information systems. Beckman Coulter is dedicated to advancing healthcare for every person and moving science, innovation and the lab forward. For more information, visit www.beckmancoulter.com.
References1 Storrow AB, Christenson RH, Nowak RM, Diercks DB, Singer AJ, Wu AHB, Kulstad E, LoVecchio F, Fromm C, Headden G, Potis T, Hogan CJ, Schrock JW, Zelinski DP, Greenberg MR, Ritchie JC, Chamberlin JS, Bray KR, Rhodes DW, Trainor D, Holmes D, Southwick PC. Diagnostic performance of cardiac Troponin I for early rule-in and rule-out of acute myocardial infarction: Results of a prospective multicenter trial. Clin Biochem 2015; 48:254-259.
2 Storrow AB, Nowak RM, Diercks DB, Singer AJ, Wu AHB, Kulstad E, LoVecchio F, Fromm C, Headden G, Potis T, Hogan CJ, Schrock JW, Zelinski DP, Greenberg MR, Christenson RH, Ritchie JC, Chamberlin JS, Bray KR, Rhodes DW, Trainor D, Southwick PC. Absolute and relative changes (delta) in troponin I for early diagnosis of myocardial infarction: Results of a prospective multicenter trial. Clin Biochem 2015; 48:260-267.
Beckman Coulter, the stylized logo, Access, AccuTnI, DxI and UniCel are trademarks of Beckman Coulter, Inc. and are registered in the USPTO.
###
RSS