Type-II myocardial infarction and chronic myocardial injury rates, invasive management, and 4-year mortality among consecutive patients undergoing high-sensitivity troponin T testing in the emergency department

Aisha Etaher; Oliver J Gibbs; Yousef M Saad; Steven Frost; Tuan L Nguyen; Ian Ferguson; Craig P Juergens; Derek Chew; John K French

doi:10.1093/ehjqcco/qcz019

Type-II myocardial infarction and chronic myocardial injury rates, invasive management, and 4-year mortality among consecutive patients undergoing high-sensitivity troponin T testing in the emergency department

Eur Heart J Qual Care Clin Outcomes. 2020 Jan 1;6(1):41-48. doi: 10.1093/ehjqcco/qcz019.

Authors

Aisha Etaher^{1

2}, Oliver J Gibbs^{1

2}, Yousef M Saad^{1

2}, Steven Frost^{3

4}, Tuan L Nguyen^{1

2}, Ian Ferguson^{2

5}, Craig P Juergens^{1

2}, Derek Chew⁶, John K French^{1

2

4}

Affiliations

¹ Department of Cardiology, Liverpool Hospital, Sydney, Elizabeth Street, Locked Bag 7103T, Liverpool BC, New South Wales 1871, Australia.
² Faculty of Medicine, The University of New South Wales, Sydney, New South Wales, Australia.
³ Faculty of Nursing, Western Sydney University, Sydney, New South Wales, Australia.
⁴ Ingham Institute for Applied Medical Research, Sydney, New South Wales, Australia.
⁵ Department of Emergency Medicine, Liverpool Hospital, Sydney, New South Wales, Australia.
⁶ College of Medicine and Public Health, Flinders University of South Australia, Adelaide, South Australia, Australia.

PMID: 31111144
DOI: 10.1093/ehjqcco/qcz019

Abstract

Aims: As assessment of patients with suspected acute coronary syndromes (ACS) in emergency departments (EDs) represents a major workload because high-sensitivity troponin (HsTn) T and I levels are frequently measured, and a minority of patients have final diagnosis of myocardial infarction (MI). We determined the relative frequencies of three patients groups: Type-I MI, Type-II MI (including acute myocardial injury).

Methods and results: Among 2738 consecutive patients with suspected ACS presenting to ED at Liverpool Hospital, Australia, between March and June 2014. We studied the use of invasive and pharmacological therapies, and 4-year outcomes. Adjudication of MI was according to the 4th universal definition as follows: (i) Type-I MI; (ii) Type-II MI (including acute myocardial injury), and (iii) chronic myocardial injury. Of 995 patients (36%) [median age 76 years (interquartile range 65-83)] with ≥2 HsTnT measurements and one >14 ng/L, 727 (73%) had chronic myocardial injury, 171 (17%) had Type-II MI, and 97 (9.7%) had Type-I MI; respective late mortality rates to 48 months were 33%, 43%, and 14% (P < 0.001). In-hospital angiography rates were 95% for patients with Type-I MI, [62% had percutaneous coronary intervention (PCI)] 24% (7% PCI) for those with Type-II MI, and 3.4% for chronic myocardial injury. On Cox modelling for mortality relative to Type 1 MI, adjusted hazard ratios were 1.94 [95% confidence intervals (CIs) 1.06-3.57]; P = 0.032 for Type 2 MI, and for chronic myocardial injury 1.14 (95% CIs 0.64-2.02); P = 0.66.

Conclusion: Among unselected patients undergoing HsTnT testing in EDs, Type-II MI including acute myocardial injury was more common than Type-I MI. Chronic myocardial injury, which occurred in three of four patients. Whereas patients with Type-II MI had higher late mortality than those with Type-I MI, after multivariable analyses mortality rates were marginally different.

Keywords: Chronic myocardial injury; HsTnT; Type-I MI; Type-II MI; mortality.

MeSH terms

Acute Coronary Syndrome / diagnosis*
Acute Coronary Syndrome / mortality
Acute Coronary Syndrome / surgery
Aged
Aged, 80 and over
Coronary Angiography
Emergency Service, Hospital*
Female
Follow-Up Studies
Humans
Male
Middle Aged
Myocardial Infarction / diagnosis*
Myocardial Infarction / mortality
Myocardial Infarction / surgery
Percutaneous Coronary Intervention*
Retrospective Studies
Risk Factors
South Australia / epidemiology
Survival Rate / trends
Time Factors
Troponin T / blood*

Substances

Troponin T