Late Outcomes of the RAPID-TnT Randomized Controlled Trial: 0/1-Hour High-Sensitivity Troponin T Protocol in
Kristina Lambrakis1,2, Cynthia Papendick2,3, John K French4
1College of Medicine and Public Health, Flinders University of South Australia, Adelaide (K.L., A.B., A.S., A.C., E.K., E.M., J.K., D.P.C.).
Insights
A rapid 0/1-hour high-sensitivity cardiac troponin T (hs-cTnT) protocol did not reduce ischemic events. However, it may increase death and myocardial infarction in patients with newly identified troponin elevations.
Area of Science:
- Cardiology
- Biomarkers
- Clinical Trials
Background:
- High-sensitivity troponin T (hs-cTnT) assays are increasingly used for acute coronary syndrome evaluation.
- Few studies compare the impact of early hs-cTnT protocols on long-term outcomes.
- This study addresses the clinical utility of a 0/1-hour unmasked hs-cTnT protocol versus a 0/3-hour masked protocol.
Purpose of the Study:
- To evaluate the late outcomes of patients managed under a 0/1-hour unmasked hs-cTnT protocol compared to a 0/3-hour masked hs-cTnT protocol.
- To determine if expedited hs-cTnT reporting improves patient outcomes.
- To assess the impact on invasive procedures and ischemic events.
Main Methods:
- A multicenter, prospective, randomized trial comparing unmasked 0/1-hour hs-cTnT reporting (<5 ng/L) with masked 0/3-hour hs-cTnT testing (≤29 ng/L).
- Included patients presenting with suspected acute coronary syndromes without ECG evidence of ischemia.
- Primary endpoint was time to all-cause death or myocardial infarction over 12 months.
Main Results:
- No significant difference in invasive coronary angiography or 12-month all-cause death/myocardial infarction between the two protocols.
- The 0/1-hour unmasked protocol was associated with reduced functional testing.
- An increase in death or myocardial infarction was observed in patients with initial troponin T levels ≤29 ng/L under the unmasked protocol (HR 1.60).
Conclusions:
- A 0/1-hour unmasked hs-cTnT protocol did not reduce ischemic events over 12 months.
- Implementation of this protocol may be associated with an increased risk of death and myocardial infarction in specific patient subgroups.
- Further research is needed to optimize the use of rapid hs-cTnT protocols.
Background:
High-sensitivity troponin assays are increasingly being adopted to expedite evaluation of patients with suspected acute coronary syndromes. Few direct comparisons have examined whether the enhanced performance of these assays at low concentrations leads to changes in care that improves longer-term outcomes. This study evaluated late outcomes of participants managed under an unmasked 0/1-hour high-sensitivity cardiac troponin T (hs-cTnT) protocol compared with a 0/3-hour masked hs-cTnT protocol.
Methods:
We conducted a multicenter prospective patient-level randomized comparison of care informed by unmasked 0/1-hour hs-cTnT protocol (reported to <5 ng/L) versus standard practice masked hs-cTnT testing (reported to ≤29 ng/L) assessed at 0/3 hours and followed participants for 12 months. Participants included were those presenting to metropolitan emergency departments with suspected acute coronary syndromes, without ECG evidence of coronary ischemia. The primary end point was time to all-cause death or myocardial infarction using Cox proportional hazards models adjusted for clustering within hospitals.
Results:
Between August 2015 and April 2019, we randomized 3378 participants, of whom 108 withdrew, resulting in 12-month follow-up for 3270 participants (masked: 1632; unmasked: 1638). Among these, 2993 (91.5%) had an initial troponin concentration of ≤29 ng/L. Deployment of the 0/1-hour hs-cTnT protocol was associated with reductions in functional testing. Over 12-month follow-up, there was no difference in invasive coronary angiography (0/1-hour unmasked: 232/1638 [14.2%]; 0/3-hour masked: 202/1632 [12.4%]; P=0.13), although an increase was seen among patients with hs-cTnT levels within the masked range (0/1-hour unmasked arm: 168/1507 [11.2%]; 0/3-hour masked arm: 124/1486 [8.3%]; P=0.010). By 12 months, all-cause death and myocardial infarction did not differ between study arms overall (0/1-hour: 82/1638 [5.0%] versus 0/3-hour: 62/1632 [3.8%]; hazard ratio, 1.32 [95% CI, 0.95-1.83]; P=0.10). Among participants with initial troponin T concentrations ≤29 ng/L, unmasked hs-cTnT reporting was associated with an increase in death or myocardial infarction (0/1-hour: 55/1507 [3.7%] versus 0/3-hour: 34/1486 [2.3%]; hazard ratio, 1.60 [95% CI, 1.05-2.46]; P=0.030).
Conclusions:
Unmasked hs-cTnT reporting deployed within a 0/1-hour protocol did not reduce ischemic events over 12-month follow-up. Changes in practice associated with the implementation of this protocol may be associated with an increase in death and myocardial infarction among those with newly identified troponin elevations. Registration: URL: https://www.anzctr.org.au; Unique identifier: ACTRN12615001379505.
More Related Videos
18:11A Research Method For Detecting Transient Myocardial Ischemia In Patients With Suspected Acute Coronary Syndrome Using Continuous ST-segment Analysis
Published on: December 28, 2012
09:21Optimized Management of Endovascular Treatment for Acute Ischemic Stroke
Published on: January 18, 2018
Related Concept Videos
01:30Acute Coronary Syndrome III: Diagnostic Studies
01:28Acute Coronary Syndrome IV: Interprofessional Care
01:30Acute Coronary Syndrome I: Introduction
01:20Blood Studies for Cardiovascular System I: Cardiac Biomarkers
The essential diagnostic tools for detecting myocardial necrosis and monitoring individuals suspected of having acute coronary syndrome (ACS) include:
Troponins
Troponins, particularly cardiac troponins I and T, are the most precise and sensitive markers of myocardial injury. They are detectable within 4-6 hours of myocardial injury and remain...
01:19Acute Coronary Syndrome II: Pathophysiology and Clinical Manifestations
01:26Acute Coronary Syndrome V: Nursing Management