CARDIAC T® Rapid Assay Of the more than 5 million people in the United States reporting to hospital emergency departments with chest pain each year, up to two-thirds are admitted for further evaluation. Of the patients subsequently discharged, 4 to 5% suffer myocardial infarction or sudden death within 72 hours of discharge (T.H. Lee et al., American Journal of Cardiology, 60:219-24, 1987). Past studies have shown that cardiac troponin T (cTnT) is a sensitive and specific marker for minor myocardial injury (H.A. Katus et al., Circulation, 83:902-12, 1991; M. Muller-Bardorff et al., Clinical Chemistry, 43:458-66, 1997). The ultra sensitive CARDIAC T Rapid Assay from Boehringer Mannheim (Indianapolis) is a second generation, one-step, disposable qualitative assay for the detection of troponin T, and can identify patients with minor myocardial damage and unstable angina who are at risk for future cardiac events.
In a recent study evaluating more than 400 patients presenting to a chest pain observation unit with chest pain and no significant electrocardiogram changes, cardiac catheterization identified coronary artery disease in virtually all patients with an elevated cTnT (C. deFilippi, R. Parmar, American Clinical Laboratory, 16:6-7,1997. The ultra sensitive CARDIAC T Rapid Assay uses two monoclonal antibodies specific to cardiac troponin T, and is the only available point-of-care testing device for the detection of troponin T. The procedure requires only 150 ml of whole blood with results obtained in less than 15 minutes, and can be used outside of the laboratory in emergency units, physician's offices, and intensive care units. The assay features a cutoff of 0.08 ng/ml, allowing physicians to detect small amounts of troponin T for improved risk stratification of patients with chest pain. Also, the assay is specific to cardiac troponin T, and shows no interference from human skeletal troponin T (<0.016% cross-reaction). The hand-held assay received FDA clearance in February 1997 and utilizes an improved antibody to troponin T.
One person who has studied cTnT and its effectiveness as a diagnostic indicator is Dr. Chris deFilippi, Assistant Professor of Medicine and Director of the Chest Pain Unit, University of Texas Medical Branch. Dr. deFilippi commented on the usage of the ultra sensitive CARDIAC T Rapid Assay, pointing out, "The bedside format of the assay provides immediate results, enabling more rapid risk stratification of patients presenting with chest pain. Usually there is significant difficulty getting laboratory results of cTnT back in less than an hour." Dr. deFilippi also added, "It definitely has its own niche." At deFilippi's Chest Pain Unit, nurses must be certified to administer the point-of-care assay.
Boehringer Mannheim is the only company to offer both quantitative and qualitative assays for the detection of troponin T. The ultra sensitive CARDIAC T Rapid Assay requires no additional reagents or equipment, and costs run from $20 to $30 per test. Boehringer also offers the ElecsysTM Immunoassay System, an automated electrochemiluminescent analyzer for detecting troponin T, CK-MB, and other critical immunoassays.
For more information contact Boehringer Mannheim at 800-852-8766 or www.boehringer-mannheim.com