Abstract 19739: Supply/Demand Type 2 Myocardial Infarction Using a High-Sensitivity Cardiac Troponin Assay with Gender-Specific Cutoffs
Introduction: Supply/demand type 2 myocardial infarction (T2MI) is frequently encountered using contemporary cardiac troponin (cTn) assays. It is expected that T2MI will become more frequent once high-sensitivity cTn (hs-cTn) assays are FDA-cleared. Little information is available about T2MI using hs-cTn assays. Our purpose was to describe the frequency, characteristics, triggers, and outcomes of T2MI using a hs-cTnI assay.
Methods: Retrospective study of 310 patients with serial hs-cTnI assay (Abbott ARCHITECT, gender-specific 99th percentiles: F:16 ng/L; M:34 ng/L) measurements was reviewed. All patients with an increased hs-cTnI underwent adjudication using the 3rd Universal Definition of MI. Clinical characteristics, resource utilization including medications and test utilization, as well as outcomes were obtained. All T2MIs underwent additional adjudication to identify the altered variable (s) within the supply/demand balance.
Results: 32 patients had an acute MI. 10 (3%) had a type 1 MI (T1MI), 22 (7%) had T2MI, 95 (31%) had non-MI with hs-cTnI increase, and 183 (59%) had no MI with no hs-cTnI increase (Table). T2MI represented 69% of all MIs (22/32). Patients with T2MI had a higher mean heart rate vs. T1MI (116 vs. 88 beats per minute, p<0.007). Anticoagulation with heparin/enoxaparin was prescribed in 50% (n=11) of T2MIs. T1MIs had higher initial hs-cTnI values (median 64 ng/L vs. 24 ng/L, p=0.42) and higher maximum hs-cTnI values (2499 ng/L vs. 190 ng/L, p<0.009) vs. T2MI. Most common triggers for T2MI were tachyarrhythmias (8/22), hypotension (8/22) and hypertension (6/22).
Conclusions: Using a hs-cTnI assay, T2MI represented 69% of all acute MIs. Despite its non-plaque rupture pathophysiology, half the patients with T2MI were prescribed anticoagulants. Tachyarrhythmias and hypotension were the most common triggers of T2MI. Our findings support the urgent need to further investigate T2MI, emphasizing studies addressing the management of T2MI.
Author Disclosures: Y. Sandoval: None. S.W. Smith: None. K.M. Schulz: None. M.M. Murakami: None. F.S. Apple: Research Grant; Modest; Research Grant Support as PI, no salary. Siemens Healthcare, Research Grant Support as PI, no salary. Abbott Diagnostics, Research Grant Support as PI, no salary. Trinity, Research Grant Support as PI, no salary. Roche Laboratories, Research Grant Support as PI, no salary. Ortho-Clinical Diagnostics, Research Grant Support as PI, no salary. Radiometer Medical, Research Grant Support as PI, no salary. Alere, Research Grant Support as PI, no salary. Davita Clinical Research, Research Grant Support as PI, no salary. Biomerieux, Research Grant Support as PI, no salary. Beckman Coulter. Honoraria; Modest; Abbott. Consultant/Advisory Board; Modest; Phillips. Consultant/Advisory Board; Significant; Instrumentation Laboratory.
- © 2014 by American Heart Association, Inc.