Faculty Collaboration Database

Type 1 and 2 Myocardial Infarction and Myocardial Injury: Clinical Transition to High-Sensitivity Cardiac Troponin I. Am J Med 2017 Dec;130(12):1431-1439.e4

Date

07/26/2017

Pubmed ID

28739197

DOI

10.1016/j.amjmed.2017.05.049

Scopus ID

2-s2.0-85027689487 (requires institutional sign-in at Scopus site)   99 Citations

Abstract

BACKGROUND: Studies addressing patients with type 2 myocardial infarction and myocardial injury, including the impact of using high-sensitivity (hs) cardiac troponin (cTn) assays on their incidence are needed.

METHODS: Ours is a prospective, observational US cohort study. Consecutive emergency department patients with serial cTnI measurements were studied. Outcomes included 180-day mortality and major adverse cardiac events, including 2-year follow-up for those with myonecrosis.

RESULTS: Among 1640 patients, using a contemporary cTnI assay, 30% (n = 497) had ≥1 cTnI >99^th percentile, with 4.7% (n = 77), 8.5% (n = 140), and 17% (n = 280) classified as type 1 myocardial infarction, type 2 myocardial infarction, and myocardial injury, respectively. Compared with patients without myonecrosis, 180-day mortality was higher for type 2 myocardial infarction (4% vs 13%, P < .0001) (adjusted hazard ratio 2.7; 95% confidence interval, 1.6-4.8; P = .0005) and myocardial injury (4% vs 11%, P < .0001) (adjusted hazard ratio 1.8; 95% confidence interval, 1.1-3.0; P = .02), both with mortality >20% at 2 years. Predictors of 2-year mortality for type 2 myocardial infarction included age, congestive heart failure, and beta-blockers. Relative to the contemporary cTnI assay, hs-cTnI had less myonecrosis (30% vs 26%, P = .003) and acute myocardial infarction (13.2% vs 10.8%, P = .032), including fewer type 2 myocardial infarctions (8.5% vs 6.3, P = .01), with no difference in myocardial injury (17% vs 15%, P = .1).

CONCLUSIONS: cTnI increases are encountered in approximately a third of patients, the majority due to nonatherothrombotic conditions. Compared with patients without myonecrosis, type 2 myocardial infarction and myocardial injury have worse short-term outcomes, with mortality rates >20% at 2 years. hs-cTnI assay does not lead to more myocardial injury or infarction.

Author List

Sandoval Y, Smith SW, Sexter A, Thordsen SE, Bruen CA, Carlson MD, Dodd KW, Driver BE, Hu Y, Jacoby K, Johnson BK, Love SA, Moore JC, Schulz K, Scott NL, Apple FS

Author

Sarah E. Thordsen MD Associate Professor in the Medicine department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Female
Heart Injuries
Humans
Incidence
Male
Middle Aged
Myocardial Infarction
Predictive Value of Tests
Prospective Studies
Sensitivity and Specificity
Troponin I