High-Sensitivity Cardiac Troponin and the Universal Definition of Myocardial Infarction

Abstract

Background: The introduction of more sensitive cardiac troponin assays has led to increased recognition of myocardial injury in acute illnesses other than acute coronary syndrome. The Universal Definition of Myocardial Infarction recommends high-sensitivity cardiac troponin testing and classification of patients with myocardial injury based on pathogenesis, but the clinical implications of implementing this guideline are not well understood. Methods: In a stepped-wedge cluster randomized, controlled trial, we implemented a high-sensitivity cardiac troponin assay and the recommendations of the Universal Definition in 48 282 consecutive patients with suspected acute coronary syndrome. In a prespecified secondary analysis, we compared the primary outcome of myocardial infarction or cardiovascular death and secondary outcome of noncardiovascular death at 1 year across diagnostic categories. Results: Implementation increased the diagnosis of type 1 myocardial infarction by 11% (510/4471), type 2 myocardial infarction by 22% (205/916), and acute and chronic myocardial injury by 36% (443/1233) and 43% (389/898), respectively. Compared with those without myocardial injury, the rate of the primary outcome was highest in those with type 1 myocardial infarction (cause-specific hazard ratio [HR] 5.64 [95% CI, 5.12–6.22]), but was similar across diagnostic categories, whereas noncardiovascular deaths were highest in those with acute myocardial injury (cause specific HR 2.65 [95% CI, 2.33–3.01]). Despite modest increases in antiplatelet therapy and coronary revascularization after implementation in patients with type 1 myocardial infarction, the primary outcome was unchanged (cause specific HR 1.00 [95% CI, 0.82–1.21]). Increased recognition of type 2 myocardial infarction and myocardial injury did not lead to changes in investigation, treatment or outcomes. Conclusions: Implementation of high-sensitivity cardiac troponin assays and the recommendations of the Universal Definition of Myocardial Infarction identified patients at high-risk of cardiovascular and noncardiovascular events but was not associated with consistent increases in treatment or improved outcomes. Trials of secondary prevention are urgently required to determine whether this risk is modifiable in patients without type 1 myocardial infarction. Clinical Trial Registration: https://www.clinicaltrials.gov . Unique identifier: NCT01852123.

High-Sensitivity Cardiac Troponin Concentrations at Presentation in Patients With ST-Segment Elevation Myocardial Infarction

“…The index diagnosis was independently adjudicated by 2 physicians on review of all clinical information, according to the Universal Definition of Myocardial Infarction. 6 Patients with type 1 STsegment elevation myocardial infarction (STEMI) were stratified according to cardiac troponin concentration at presentation using a validated risk-stratification threshold (5 ng/L), 1 the sex-specific 99th percentile, and the European Society of Cardiology (ESC) 0 of 1 hour pathway rule-in threshold (52 ng/L). 4 Posterior STEMI was defined as those with STEMI and an acute occlusion of the circumflex, obtuse marginal, or posterior left ventricular artery on angiography.…”

EAPCI Position Statement on Invasive Management of Acute Coronary Syndromes during the COVID-19 pandemic

“…4 5 Implementation of high sensitivity (hs)-cTn assays, along with the application of the 4 th Universal definition of myocardial infarction (MI), has led to an increased accuracy in the differentiation between type 1 MI, type 2 MI, and acute and chronic myocardial injury. 6 However, no cut-off values for cTn can reliably differentiate between acute myocardial injury and different types of MI. Whilst myocardial injury and type 2 MI are associated with a worse long-term prognosis than type 1 MI, 7 there is no consensus regarding how to manage these patients, except for treatment of the underlying disease.…”

Determination of high sensitive cardiac troponin I 99th percentile upper reference limits in a healthy Pakistani population

“… 1 Introducing high sensitive cTn assays has contributed to improved awareness of myocardial damage other than acute coronary syndromes. 2 Myocardial injury is by far the most frequent cause of irregular troponin findings, and its incidence is expected to rise with an aging population, increased cardiac comorbidity, and increased troponin assay sensitivity. 3 …”