Coronary angiography findings in emergency department chest pain patients undergoing angiography despite hs-cTnT-based early rule-out angiography after hs-cTnT rule-out in ED chest pain

BACKGROUND: High-sensitivity cardiac troponin (hs-cTn) algorithms are established for early rule-out of acute myocardial infarction, but coronary angiographic (CAG) findings in emergency department (ED) patients undergoing invasive evaluation despite fulfilling rule-out criteria remain insufficiently described. OBJECTIVE: To characterise the coronary anatomy and clinical profile of ED patients with chest pain undergoing urgent CAG despite fulfilling hs-cTnT-based early rule-out criteria. METHODS: This retrospective single-centre study included adults with suspected acute coronary syndrome from 1 January 2020 to 1 January 2023. All patients fulfilled the serial European Society of Cardiology 0/1-hour rule-out pathway, defined as baseline hs-cTnT <12 ng/L and a 1-hour absolute change <3 ng/L. Patients undergoing urgent CAG during index hospitalisation comprised the angiographic cohort. Findings were categorised as significant stenosis (≥70% in a major non-left-main epicardial artery or ≥50% in the left main), intermediate stenosis (50%-69% in a non-left-main artery) or non-obstructive coronary artery disease (<50%). Baseline and 1-hour hs-cTnT concentrations, 1-hour and relative 1-hour changes, History, ECG, Age, Risk factors and Troponin (HEART) scores and angiographic findings were compared. RESULTS: Of 646 patients, 376 underwent urgent CAG. Significant stenosis was found in 109 (29.0%), intermediate stenosis in 220 (58.5%) and non-obstructive disease in 47 (12.5%). Baseline and 1-hour hs-cTnT concentrations and HEART scores differed significantly across angiographic categories, with the highest values in the significant stenosis group and the lowest in the non-obstructive group. The 1-hour and relative 1-hour hs-cTnT changes also differed overall, although significant pairwise differences were limited to the intermediate and non-obstructive groups. Relative hs-cTnT change showed limited discrimination for non-obstructive disease, whereas the HEART score showed moderate discrimination for ≥50% angiographic stenosis. CONCLUSIONS: Among selected ED patients undergoing urgent CAG despite hs-cTnT-based rule-out, intermediate or significant stenosis was common. These findings descriptively characterise coronary anatomy in this cohort but do not establish culprit-lesion status, functional significance, appropriateness of angiography or failure of the hs-cTnT rule-out algorithm.