Early rule-out and rule-in of myocardial infarction using sensitive cardiac Troponin I

• Published in: International journal of cardiology 2015-09, Vol.195, p.163-170
• Main Authors: Druey, Sophie, Wildi, Karin, Twerenbold, Raphael, Jaeger, Cédric, Reichlin, Tobias, Haaf, Philip, Rubini Gimenez, Maria, Puelacher, Christian, Wagener, Max, Radosavac, Milos, Honegger, Ursina, Schumacher, Carmela, Delfine, Valentina, Kreutzinger, Philip, Herrmann, Thomas, Moreno Weidmann, Zoraida, Krivoshei, Lian, Freese, Michael, Stelzig, Claudia, Isenschmid, Cyril, Bassetti, Stefano, Rentsch, Katharina, Osswald, Stefan, Mueller, Christian
• Format: Article
• Language: English
• Subjects: Acute myocardial infarction; Aged; Algorithm; Algorithms; Biomarkers - analysis; Biomarkers - blood; Cardiovascular; cTnI; Early Diagnosis; Emergency Service, Hospital - statistics & numerical data; Female; Humans; Male; Middle Aged; Myocardial Infarction - blood; Myocardial Infarction - diagnosis; Prospective Studies; Reproducibility of Results; Rule-in; Rule-out; Time-to-Treatment - standards; Time-to-Treatment - statistics & numerical data; Troponin I - analysis; Troponin I - blood
• ISSN: 0167-5273; 1874-1754
• DOI: 10.1016/j.ijcard.2015.05.079

Abstract Background It is currently unknown, whether and to what extent sensitive cardiac troponin (s-cTn) allows shortening of the time required for safe rule-out and rule-in of acute myocardial infarction (AMI). Methods We aimed to develop and validate early rule-out and rule-in algorithms for AMI using a thoroughly-examined and commonly used s-cTnI assay in a prospective multicenter study including 2173 patients presenting to the emergency department with suspected AMI. S-cTnI was measured in a blinded fashion at 0 h, 1 h, and 2 h. The final diagnosis was centrally adjudicated by two independent cardiologists. In the derivation cohort (n = 1496), we developed 1 h- and 2 h-algorithms assigning patients to “rule-out”, “rule-in”, or “observe”. The algorithms were then prospectively validated in the validation cohort (n = 677). Results AMI was the adjudicated diagnosis in 17% of patients. After applying the s-cTnI 1 h-algorithm developed in the derivation cohort to the validation cohort, 65% of patients were classified as “rule-out”, 12% as “rule-in”, and 23% to “observe”. The negative predictive value for AMI in the “rule-out” group was 98.6% (95% CI, 96.9–99.5), the positive predictive value for AMI in the “rule-in” group 76.3% (95% CI, 65.4–85.1). Overall, 30-day mortality was 0.2% in the “rule-out” group, 1.0% in the “observe” group, and 3.0% in the “rule-in” group. Similar results were obtained for the 2 h-algorithm. Conclusion When used in conjunction with other clinical information including the ECG, a simple algorithm incorporating s-cTnI values at presentation and after 1 h (or 2 h) will allow safe rule-out and accurate rule-in of AMI in the majority of patients.