Complete Proximal Right Coronary Artery Occlusion in a Patient With Normal Initial Acute Coronary Syndrome (ACS) Workup: The Diagnostic Value of Clinical Judgment and Risk Stratification.

Acute coronary syndromes (ACS), including unstable angina, non-ST-elevation myocardial infarction (NSTEMI), and ST-elevation myocardial infarction (STEMI), are major causes of emergency department (ED) visits and are typically evaluated using clinical presentation, electrocardiogram (EKG), and cardiac biomarkers such as troponin. We present the case of a 47-year-old male with hyperlipidemia and a coronary artery calcium score (CACS) >200 who reported worsening exertional chest pain and dyspnea. Despite a normal EKG, serial troponins, prior stress test, and echocardiogram, his symptoms raised clinical concern. He was admitted with suspected unstable angina, and cardiac catheterization revealed a 100% occlusion of the proximal right coronary artery (pRCA), successfully treated with a drug-eluting stent. His symptoms resolved completely within three months. This case highlights the limitations of relying solely on non-invasive testing and biomarkers in detecting significant coronary artery disease (CAD), especially when collateral circulation is present. It also emphasizes the value of clinical judgment and the integration of risk stratification tools such as the Thrombolysis in Myocardial Infarction (TIMI) and​​​​​​​ History, Electrocardiogram, Age, Risk factors, and Troponin (HEART) scores. Ultimately, this case underscores the need for a vigilant, individualized approach to chest pain evaluation, where early invasive diagnostics may be warranted even in the absence of definitive initial findings.