Implementation of High-Sensitivity Cardiac Troponin: Challenges From the International Experience.

OBJECTIVE: Implementation of the newly approved high-sensitivity cardiac troponin (hs-cTn) in the United States presents a challenge for clinical practice. Sex-specific cutoffs, clinical protocols, and workflows will likely require modifications before implementation. METHODS: We conducted a cross-sectional survey of international physicians and laboratorians already utilizing hs-cTn for the evaluation of acute myocardial infarction. RESULTS: Twenty-two of 54 (41%) eligible participants completed the survey, representing 9 countries and 18 hospitals. All reported successful hs-cTn implementation and diagnostic utility (mean 8.6 + 1.2 out of 10 for best implementation). The major perceived benefit was more rapid evaluation of acute myocardial infarction (14/19, 74%), and the most frequently cited limitation was an increase in the number of measurable hs-cTn values that required further evaluation (8/18, 44%). Institutions using the hs-cTnI assay favored sex-specific cutoffs (5/6, 83%), whereas institutions employing the hs-cTnT assay favored a combined cutoff (12/12, 100%). Timing of serial hs-cTn measurements varied, with 0-3 hours (8/17, 47%) most frequent, followed by 0-2 hours (4/17, 24%), 0-1 hour (3/17, 18%), and other (2/17, 12%). CONCLUSIONS: Our survey of hs-cTn implementation at international institutions reveals satisfaction with new assays but reflects important variations in clinical practice. The use of sex-specific vs. combined cutoffs and timing of serial hs-cTn measurements varies across institutions and are subjects that United States centers must define without consensus from international practices.