Posterior myocardial infarction caused by superdominant circumflex occlusion over an absent right coronary artery: Case report and review of literature

RATIONALE: Congenital agenesis of the right coronary artery (CARCA) initially presenting as acute myocardial infarction (AMI) due to total occlusion is a rare clinical condition that can lead to severe complications, including death. We report a case of successful percutaneous coronary intervention (PCI) in a patient with this condition. PATIENT CONCERNS: A 57-year-old man was admitted to our center with chest pain that had occurred several hours prior. Since he was initially diagnosed with AMI with ST-segment elevation, we promptly commenced coronary angiography (CAG). DIAGNOSIS: CAG revealed the absence of a right coronary artery (RCA). In the left coronary cusp area, the left circumflex coronary artery (LCX) was occluded totally. INTERVENTIONS: We performed PCI for total occlusion of the proximal part of the LCX. Follow-up CAG showed a superdominant branch of the LCX, sprouting into the RCA territory. OUTCOMES: The patient was discharged uneventfully after successful PCI. LESSONS: CARCA with AMI, which is an extremely unusual case, can be fatal; however, PCI seems to be an effective treatment option.