Can hs-cTn Reclassify Non-ST Elevation ACS?

A 60-year-old male patient with a history of dyslipidemia presented to the emergency department with worsening chest pain. He first developed chest pain 1 week prior while riding his bicycle. He described left-sided dull chest pain with a pressure quality that radiated down his left arm. The pain lasted 10 minutes and resolved with rest. Over the subsequent week, he developed chest pain with less exertion, including walking up a flight of stairs and, more recently, preparing for bed. He now presented with chest pain that started 6 hours ago and occurred while lying in bed, again lasting approximately 10 minutes. His medications include aspirin 81 mg and fish oil daily. He is a nonsmoker and works as an electrician. He has a family history of early coronary artery disease; his father died from a myocardial infarction (MI) at the age of 55.

On arrival, his blood pressure was 145/80 mmHg, and his heart rate was 67 bpm. Physical exam demonstrated a man in no acute distress lying comfortably in bed. Cardiac exam demonstrated regular rate and rhythm with normal heart sounds and without murmurs or rubs. He had no jugular venous distention. His lungs were clear to auscultation, and he had no peripheral edema.

A 12-lead electrocardiogram (ECG) demonstrated normal sinus rhythm and was otherwise unremarkable with no ischemic changes. Chest x-ray was normal. Laboratory work-up obtained included a hemoglobin of 14.5g/dL, creatinine of 1.1mg/dL (estimated glomerular filtration rate >60 mL/min/BSA), and an initial fourth generation cardiac troponin T (cTnT) of <0.01 ng/mL (99th percentile upper reference limit <0.01 ng/mL) at presentation. He was admitted for concerns of suspected acute coronary syndrome (ACS) and underwent serial cTnT measurements at 3 and 6 hours, which were both <99th percentile (<0.01 ng/ml).

Based on the above information, what is the most appropriate next step?

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