Rare, but clinically significant cases of abnormalities of coronary arteries: "pathological valves".

The most commonly occurring pathology of carotid arteries (CAs) is an atherosclerotic stenosing lesion thereof (accounting for up to 80% of all cases), to be immediately followed by pathological tortuosity of carotid arteries. Of much less frequent occurrence are vasculitides, vasculopathies and thrombotic lesions [1-4]. The authors revealed rarely encountered, yet clinically significant abnormalities of the CA structure, which we called "pathological valves" (PVs). However, we failed to find any published reports describing the pathology concerned in the available literature dedicated to ultrasonographic, roentgenological diagnosis or surgical management, hence our article. The present study was aimed at investigating the structure of the wall of the common carotid artery in the area of its bifurcation in the presence of blood flow obstruction caused by nonatherosclerotic alterations detected during ultrasonographic examination and confirmed by angiography. The obtained results were then compared with the findings of clinical studies and the morphological picture of the operative material. There were twenty-six cases of the so-called "pathological valves" amongst more than six thousand ultrasonographic examinations of the brachiocephalic arteries we performed. All the patients operated on turned out to have a history of transient ischaemic attacks (TIAs) or degree I-II cerebral infarctions in the respective carotid basin. Both morphological and histological examinations revealed that the "pathological valves" consisted of the interrupted, not forming an entire, solid layer, collagenous and elastic ribles covered with the endothelium similar in the morphological structure to that of the tunica intima of the artery.