Journal of Cardiovascular, Neurovascular & Stroke https://mycvns.com 7 FETAL POSTERIOR COMMUNICATING ARTERY AS A CONDUIT FOR CONCURRENT ANTERIOR AND POSTERIOR CIRCULATION INFARCT: A CLINICAL CASE REPORT Mohamed Azlam Micdhadhu 1* , Kho Ko Hin 1 , Mazeda Murad 2 , Irene Looi 1 1 Internal Medicine Department, Hospital Seberang Jaya. 2 Radiology Department, Hospital Seberang Jaya. *Corresponding Author: Dr. Mohamed Azlam Micdhadhu, Internal Medicine Department, Hospital Seberang Jaya, Pulau Pinang, Malaysia. Tel: +604-3827333 DOI: https://doi.org/10.32896/cvns.v3n4.7-11 Published: 31.12.2021 Article History: Received October 30, 2020; Revised October 07, 2021; Accepted October 28, 2021 ABSTRACT Fetal type posterior cerebral artery (FTPCA) is a variant of posterior circulation of brain, in which the distal part of posterior cerebral artery (PCA) is perfused by a branch of internal carotid artery (ICA) via fetal posterior communicating artery (fetal PCOM). In the presence of fetal PCOM, a paradoxical concurrent infarction of anterior and posterior circulation may happen. We report a 67-year-old man who presented with sudden onset right sided weakness and aphasia, with National Institutes of Health Stroke Scale (NIHSS) score of 22 and clinically diagnosed to have left total anterior circulation infarct (TACI). Subsequently, he received IV Alteplase as a standard hyperacute ischemic stroke treatment. Computed tomography angiography (CTA) of brain showed left FTPCA with prominent left fetal PCOM. Subsequent computed tomography (CT) of brain showed concurrent left middle cerebral artery (MCA) and PCA territories infarct. CTA brain is commonly done in ischemic stroke cases to assess presence of large vessel occlusions and intracranial or extracranial atherosclerotic disease. However, this case depicts its additional role in detecting anatomical variants of cerebral circulation. In terms of clinical importance, presence of multiple territories infarction portends a poorer neurological outcome. Keywords: Infarct BACKGROUND Posterior cerebral artery (PCA) is an important branch of basilar artery in posterior circulation of the brain. It functions to supply the occipital lobe, the inferomedial temporal lobe, and portions of the posterior inferior parietal lobe. [1] Fetal origin of the PCA is a common variant in the posterior cerebral circulation, with an estimated prevalence of 15-32% of individuals. [2] This common variant is mainly detected only after a patient has suffered an ischemic stroke or when a non- invasive or invasive cerebral angiography is performed for various indications. Fetal type PCA (FTPCA) denotes bulk of blood supply to PCA territory arising from internal carotid artery (ICA) via posterior communicating artery (PCOM) with absent or hypoplastic P1 segment of PCA. This variant of PCOM is called fetal PCOM. Van Raamt et al. have proposed the term full fetal type PCA (full FTPCA) for total absence of P1 segment, while partial FTPCA for hypoplastic P1 segment. In both circumstances, the posterior communicating artery appears larger than usual on CTA brain. [3] Although FTPCA is a normal variant; it results in the lack of proper collaterals and larger than usual posterior communicating artery may pose an