Lab Medicine Significance 6/10

HEART Pathway Performs Equally Well With High-Sensitivity Troponin I as With Conventional Assays

A secondary analysis of the HEART Pathway RCT found that substituting high-sensitivity cardiac troponin I for conventional troponin I maintained identical test characteristics: 100% sensitivity and 100% NPV for 30-day MACE, with a 45% early discharge rate. However, using hs-cTnT missed one myocardial infarction, dropping sensitivity to 91%. These findings support hs-cTnI integration into the HEART Pathway without loss of diagnostic safety.

The original study

Use of the HEART Pathway with high sensitivity cardiac troponins: A secondary analysis.

Authors
Mahler SA, Stopyra JP, Apple FS, Riley RF, Russell GB, Hiestand BC, et al.
Journal
Clinical biochemistry
Type
Journal Article, Randomized Controlled Trial
PMID
28087371
Read the original study →

Original abstract

OBJECTIVES: The HEART Pathway combines a decision aid and serial contemporary cardiac troponin I (cTnI) measures to achieve >99% sensitivity for major adverse cardiac events (MACE) at 30days and early discharge rates >20%. However, the impact of integrating high-sensitivity troponin (hs-cTn) measures into the HEART Pathway has yet to be determined. In this analysis we compare test characteristics of the HEART Pathway using hs-cTnI, hs-cTnT, or cTnI. DESIGN & METHODS: A secondary analysis of participants enrolled in the HEART Pathway RCT was conducted. Each patient was risk stratified by the cTn-HEART Pathway (Siemens TnI-Ultra at 0- and 3-h) and a hs-cTn-HEART Pathway using hs-cTnI (Abbott) or hs-cTnT (Roche) at 3-h. The early discharge rate, sensitivity, specificity, and negative predictive value (NPV) for MACE (death, myocardial infarction, or coronary revascularization) at 30days were calculated. RESULTS: hs-cTnI measures were available on 133 patients. MACE occurred in 11/133 (8%) of these patients. Test characteristics for the HEART Pathway using serial cTnI vs 3hour hs-cTnI were the same: sensitivity (100%, 95%CI: 72-100%), specificity (49%, 95%CI: 40-58%), NPV (100%, 95%CI: 94-100%), and early discharge rate (45%, 95%CI: 37-54%). The HEART Pathway using hs-cTnT missed one MACE event (myocardial infarction): sensitivity (91%, 95%CI: 59-100%), specificity (48%, 95%CI: 39-57%), NPV (98%, 95%CI: 91-100%), and early discharge rate (45%, 95%CI: 37-54%). CONCLUSIONS: There was no difference in the test characteristics of the HEART Pathway whether using cTnI or hs-cTnI, with both achieving 100% sensitivity and NPV. Use of hs-cTnT with the HEART Pathway was associated with one missed MACE.