Ischemic stroke related to intracranial branch atheromatous disease and comparison with large and small artery diseases.

Background: The mechanism of ischemic stroke in intracranial branch atheromatous disease (BAD) is different from large artery atherothrombotic disease (LAD) or lacunar infarction (LACI). The concept of BAD is underused in clinical practice and research.

Methods: Patients admitted over 24-months with ischemic stroke caused by atherosclerotic disease were reviewed retrospectively and classified according to radiological±clinical criteria into LAD, BAD and LACI. The BAD cases were further divided into 5 BAD syndromes. Clinical characteristics, vascular risk factors, results of vascular workup and outcome among these subgroups were compared.

Results: 123 cases of LAD (17% of all stroke patients or 33% of all studied patients), 147 BAD (20% or 40%) and 102 LACI (14% or 27%) presented during the study period. Compared to LAD, BAD patients had milder neurological deficits, were less often diabetic and carotid stenosis was less common, while stenosis of the intracranial arteries was more frequent in BAD as compared with LACI patients. Outcome in BAD patients was intermediate between LAD and LACI. Comparisons among the BAD syndromes indicated they were homogenous conditions.

Conclusions: BAD is the most prevalent ischemic stroke subtype in our cohort. The homogeneity among the BAD syndromes suggests they might represent a distinctive stroke entity.