A Rapid Point-of-Care Cardiac Marker Testing Strategy Facilitates the Rapid Diagnosis and Management of Chest Pain Patients in the Emergency Department

• Published in: American journal of clinical pathology Vol. 129; no. 5; pp. 788 - 795
• Main Authors: STRAFACE, Angela L, MYERS, John H, KIRCHICK, Howard J, BLICK, Kenneth E
• Format: Journal Article
• Language: English
• Published: Chicago, IL American Society of Clinical Pathologists 01-05-2008
• Subjects: Algorithms; Biological and medical sciences; Biomarkers - blood; Cardiology. Vascular system; Chest Pain - diagnosis; Chest Pain - etiology; Coronary heart disease; Creatine Kinase - blood; Emergency Medical Services - methods; Female; Heart; Humans; Investigative techniques, diagnostic techniques (general aspects); Length of Stay; Male; Medical sciences; Middle Aged; Myocardial Infarction - blood; Myocardial Infarction - complications; Myocardial Infarction - diagnosis; Myoglobin - blood; Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques; Point-of-Care Systems; Sensitivity and Specificity; Treatment Outcome; Troponin I - blood; Heart; Human; Myocardial infarction; Point-of-care testing; Cardiac markers; Acute; Biological marker; Cardiovascular disease; Biological indicator; Turnaround times; Coronary heart disease; Myocardial disease; Anatomic pathology; Clinical management; Emergency department; chest pain; Point of care testing; Strategy; Circulatory system; Diagnosis; Acute myocardial infarction
• ISSN: 0002-9173; 1943-7722
• DOI: 10.1309/9GGNMURLJWJD88W3

We compared a rapid, point-of-care multimarker protocol with a single and serial troponin I (TnI)-only protocol in 5,244 patients admitted to the emergency department with chest pain. The diagnosis of acute myocardial infarction (AMI) was based on a doubling myoglobin level accompanied by at least a 50% increase in the creatine kinase (CK)-MB level with no detectable TnI; a doubling of myoglobin level together with any detectable TnI; or a TnI level of 0.4 ng/mL (0.4 microg/L) or more, irrespective of myoglobin or CK-MB results. By using these new criteria, 145 of 148 cases were positive for AMI (positive predictive value [PPV], 92.4%) and 3 were negative, which were also negative by the core laboratory TnI assay. Twelve confirmed non-AMI cases were positive by the new protocol, with 10 of 12 confirmed by the core laboratory as positive for TnI. The negative predictive value (NPV) was 99.9% the overall diagnostic accuracy was 99.7%. The TnI-only protocol had a sensitivity of 68.2% with an NPV of 99.1%. With lower TnI-only cutoffs, 4 patients had false-negative results, and a PPV of 36.4% was observed. Our rapid multimarker protocol seems superior to a TnI-only approach for rapidly triaging patients with chest pain or AMI.