Introduction:The anomalous origin of the right coronary artery (RCA) from the left coronary sinus coursing between the aorta and the pulmonary trunk is rare, but may cause myocardial ischemia and sudden death. Multislice CT coronaryangiography offers the possibility to visualize anomalous coronary artery origin non-invasively in details. Case Illustration: A 54-year-old man with a history of arterial hypertension, and hypercholesterolemia began to present with typical chest pain. After some non-invasive examination, he had coronary angiographythat revealed 70% stenosis at mid intermediate artery, normalLMCA, LAD and LCX. Ostium of RCA was found near the left valsava sinus afterrepeated cannulation attempts, no stenosis was found at RCA. After successful revascularization at intermediate artery, patient still had typical chest pain with positive ischemic response in treadmill test. Multislice CT coronary angiography was performedto evaluate the etiology of chest pain. The scan showed patent stent at intermediate artery and anomalous RCA origin from the left coronary sinus withacute angle take-off, luminal narrowing of the osteal-proximal part, as well as luminal compression between the ascending aorta and the pulmonary trunk (an interarterial course) while RCA appeared as dominant vessel. These features were considered as malignant coronary anomaly that could lead to the recommendation of surgical correction. Discussion: Accurate recognition and documentation of coronary artery anomalies are essential to determine the significance of such findings and to avoid furtherclinical complications. Multislice CT coronary angiography is a non-invasive imaging modality that can easily and precisely depict the origin and course of coronary artery anomalies as well as its relationship with adjacent structures. (J Kardiol Indones. 2014;35:274-7)Pendahuluan Kasus anomali dimana arteri koroner kanan berasal dari sinus koronarius kiri yang melintas diantara aorta dan arteri pulmonalis adalah jarang, namun dapat menyebabkan iskemia miokardium dan kematian jantung mendadak. Pencitraan dengan multislice CT angiografi koroner dapat mendeteksi anomali arteri koroner secara detail dan non invasif. Ilustrasi Kasus Laki laki berusia 54 tahun dengan riwayat hipertensi dan hiperkolesterolemia datang dengan keluhan nyeri dada tipikal. Setelah dilakukan beberapa pemeriksaan non invasif, pasien menjalani angiografi koroner dan didapatkan stenosis 70% pada arteri mid intermediate, normal arteri koroner cabang utama, arteri koroner anterior desendens, dan arteri koroner sirkumfleksa. Ostium arteri koroner kanan ditemukan setelah beberapa usaha kanulasi dan terletak dekat sinus valsava kiri. Tidak didapatkan stenosis pada arteri koroner kanan. Setelah dilakukan revaskularisasi pada arteri intermediate dengan sukses, pasen masih mengeluh nyeri dada tipikal dengan respon iskemik positif pada uji latih jantung. MSCT angiografi koroner dilakukan untuk evaluasi etiologi nyeri dada. Hasil MSCT angiografi koroner menunjukkan bahwa stent pada arteri int...