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Please check out our Clinical Diagnostics section or Point of Care Diagnostic Devices section to find manufacturers that sell these products
Cardiac Biomarker Guidelines
Clinical guidelines from the disciplines of cardiology and laboratory medicine recommend the measurement of cardiac biomarkers as soon as possible in patients who present with suspected myocardial infarction. The measurement of cardiac troponins is especially useful in the large fraction of patients presenting with acute coronary syndrome (ACS) who have negative 12-lead EKGs. About 30% of patients previously considered to have unstable angina are now given a diagnosis of non-ST elevation myocardial infarction (NSTEMI) based on their cardiac troponin levels. Troponin levels additionally aid in risk stratification.
The development of accelerated protocols for diagnosing ACS in patients with chest pain necessitates the reduction of turnaround time (TAT) for cardiac marker results. Recommendations for the optimum TAT vary from 30 to 60 min. With regard to TAT, quantitative point-of-care (POC) assays that directly assay anticoagulated whole blood provide a good alternative to central laboratory testing that takes more than 1 hr to produce results. In addition, there is some evidence that POC testing in the emergency department can reduce the time to hospitalization or to discharge.
All Point-of-Care Testing Devices Include Point-of-Care Troponin
- Siemens USA (Malvern, PA) offers the Stratus® CS Acute Care™ Diagnostic System, which comprises the Stratus CS Analyzer and a broad range of single, ready-to-use, quantitative dendrimer-enhanced radial partition immunoassays to aid in the differential diagnosis of chest pain. The assays are for high-sensitivity tropinin-I, CK-MB mass, myoglobin, NT-proBNP, D-dimer, and CardioPhase™ hsCRP. The company states that its high-sensitivity tropinin-I assay was the first marketed assay to meet the 2005 American College of Cardiology/American Heart Association (ACC/AHA) guidelines (imprecision level of ≤10% at the 99th percentile of normal). All the assays except for the D-dimer assay can be run on a single heparinized whole blood sample on a single run. The blood samples are processed by on-board centrifugation, and the analyzer is a random-access analyzer—no fixed assay panels. The TAT to first result is 14 min, and the TAT for each subsequent result is 4 min.
- Response Point of Care Inc. (Charlotte, NC) offers the RAMP® system, a proprietary platform technology that combines a portable fluorescence detection system with simple lateral-flow immunoassays designed as single-use disposable test cartridges. There are two readers: the high-throughput multiport Ramp 200 that accommodates one Control Module and three Test Modules, and the Ramp Reader, which is a fully portable point-of-care testing device. Both quantitative and qualitative results are displayed, and a flexible interface allows network transfer of patient results and quality control data to external systems. The cardiac tests that are available in the United States include the Ramp Tropinin I, NT-proBNP, Myoglobin, and CK-MB Tests. The Ramp D-Dimer Test is available for countries in the European Union. To perform the test, a diluted blood sample is added to the sample well of the test cartridge, the red blood cells are retained, and the plasma migrates. Fluorescent-dyed latex particles coated with antigen-specific antibodies bind to antigen in the sample. Antigen-bound particles are captured in the detection zone and excess particles are captured at the internal control zone by anti-immunoglobins. The fluorescence of the detection and internal control zones is measured by the RAMP Readers. Test cartridges for each biomarker are provided in individual kits (25 cartridges/kit). Results are available in 10–20 min, depending on the assay.
- Roche Diagnostics (Indianapolis, IN) offers the Trop T® Sensitive Rapid Assay, which provides qualitative (yes/no) results in 15 min. The company claims that the test has a wide diagnostic spectrum, aiding in the diagnosis of myocardial infarction even 14 days after the myocardial event, providing risk assessment for patients with unstable angina, and detecting minor myocardial damage. The test is based on a specific immunologic reaction, and requires 150 μL of anticoagulated venous whole blood.
Please check out our Clinical Diagnostics section or Point of Care Diagnostic Devices section to find manufacturers that sell these products