Having a Heart Attack? New Troponin Test May Tell Quickly
If you experience acute chest pain and are rushed to the emergency department, the burning question in your mind is likely, “Am I having a heart attack?” A new, next-generation troponin I test (assay) may quickly provide that vital information for you and your doctors.
The new troponin I test is highly sensitive
Along with asking questions about symptoms, health history, and family history of heart disease, the first tests healthcare providers perform to diagnose a heart attack are an electrocardiogram (ECG) and blood tests. The latter are done to identify specific heart enzymes or proteins that leak into the bloodstream when the heart has been damaged by a heart attack.
Troponin I is one of those proteins. Even a slight increase in troponin I means there has been damage done to the heart. A diagnosis of heart attack (myocardial infarction, or MI) is based primarily on the presence of elevated troponin levels that exceed the 99th percentile and show an increase or decrease over time.
Although doctors currently use a troponin I assay to help diagnose heart attack, the new, next-generation test may speed up the ability to make a diagnosis to within three hours, and therefore allow doctors to more quickly treat patients. Heart attack patients who are treated rapidly and aggressively benefit the most.
The new text can detect the relative change in troponin I levels in the first three hours with a positive predictive value of 95.8% when combined with information gathered from admission. Overall, the new assay provided more diagnostic information for doctors than did the older test, including lower concentrations of troponin I.
The researchers arrived at their conclusions after studying 1,818 patients with suspected acute coronary syndromes. In addition to measuring for troponin I, the patients were also tested for 11 other cardiac markers at 3 and 6 hours after admission.
It should be noted that the older troponin I test is also highly accurate, and that both troponin tests proved superior to the other markers measured for in the study.
The authors of the new study noted that their findings indicate that the new troponin I test can make it possible to accurately identify heart attack as well as rule it out as soon as 3 hours after admission to the hospital in a large number of patients who have chest pain. And that could mean more patients will receive faster treatment for heart attack.
Keller T et al. Journal of the American Medical Association 2011; 306: 2684-93
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