High-Sensitivity Troponin Assay Safely Rules Out MI
By Liisa Vexler
Swedish emergency doctors conducted a study of more than 14,000 consecutive patients presenting at the ER with chest pain and found that a negative high-sensitivity troponin assay plus an ECG with no ischemic changes reliably ruled out myocardial infarction (MI). This type of assay, available in Europe, is currently not available in the United States.
Dr. Nadia Bandstein of Stockholm’s Karolinska University Hospital presented the research findings at the 2014 American College of Cardiology conference in Washington DC, noting that the absence of detectable levels of cardiac troponin, defined as <5 ng/L, was also a 100% accurate predictor of survival at 30 days post ER visit.
Of the study subjects with negative assay results who were admitted, greater than two thirds were discharged the same day, half of whom left with a diagnosis of “unspecified chest pain.” Dr. Bandstein says, "We believe that with this strategy, 20 percent to 25 percent of admissions to hospitals for chest pain may be avoided.” This assay could help her hospital "avoid 600 to 700 hospitalizations every year."
In an interview with Medscape, Cedars-Sinai Medical Center’s Dr. Prediman K. Shah, a cardiologist who is not connected with the research in question, noted that this is a retrospective, observational study conducted at one hospital and it is therefore difficult to generalize the findings at this point. However, he did say that, "Its size is so large and is [from] a single center, which means they probably have better control on the data than in a multicenter trial. I think that's probably why we're giving it a little more weight" than a similar study might receive. He looks forward to seeing the results validated in a future prospective study.
US physicians have no experience with hs-Troponin assays, but this could be an exciting avenue of further study and future clinical practice.