Abstract 3133: Prognostic Utility of Detectable Plasma Cardiac Troponin I in Stable Patients Undergoing Elective Coronary Angiography Without Myocardial Infarction
Background: Elevated cardiac troponin (cTnI) level is one of the diagnostic criteria for acute coronary syndromes (ACS) and portends a poor prognosis. The prognostic value of cTnI levels below the diagnostic range has not been established.
Methods: We examined cTnI levels below the diagnostic range of ACS (<0.03 ng/mL) and their relationship with incident major adverse cardiovascular events over 3-year follow-up in 2,588 patients undergoing elective coronary angiography without myocardial infarction. cTnI was measured using the cTnI assay from the Abbott Architect platform (Abbott Diagnostics Inc, Abbott Park IL).
Results: In our cohort (mean age 63 years, 64% male, 68% with hypertension, 30% with diabetes mellitus, mean creatinine clearance 96ml/min), the mean and median cTnI were 0.005±0.007 ng/mL and 0.002 ng/mL, respectively. Sixty-three percent of patients (1,636/2,588) had detectable cTnI levels, corresponding to a 2.5-fold increased risk of major adverse clinical events (death, non-fatal myocardial infarction, and stroke) compared to those with no detectable cTnI levels (see Figure⇓). After adjusting for traditional risk factors including Framingham risk score, C-reactive protein, and creatinine clearance, the presence of any detectable cTnI remained significantly associated with incident major long-term major adverse cardiac events (Hazard ratio 2.02; 95%CI 1.50 – 2.73, p<0.001).
Conclusions: In stable patients undergoing elective coronary angiography without myocardial infarction, detectable cTnI by high sensitivity assay below its diagnostic range provides independent risk prediction of long-term adverse cardiac events.