[Characteristics of cerebral microembolic signals and focal lesions of the brain in different causes of cardiogenic embolism]. / Kharakteristika tserebral'nykh mikroémbolicheskikh signalov i ochagovoe porazhenie golovnogo mozga pri razlichnykh tipakh istochnikov kardiogennoi émbolii.

ABSTRACT

To study quantitative and qualitative characteristics of microembolic signals (MES) and specific features of a focal damage to the brain depending on the site of the embolic substrate in patients with cardioembolic stroke (CES), we examined 84 patients who survived CES. 38 (45.2%) of them had an acute stage, 46 (54.8%)--a residual stage. Group 1 comprised 42 patients with cardial pathology characterized by intrachamber formation of the embolus and 2 patients with an open oval window. Group 2 consisted of 40 (48%) patients with diseases promoting formation of emboli on the cardiac valves. The highest frequency, intensity and duration of MES in CES were registered in patients of group 2 while the number of ischemic focuses was greater in patients of group 1. This may be explained by the fact that intensity and duration of cardiogenic MES depend more on acoustic density of the embolus than on its size. Therefore, the site of the embologenic substrate together with quantitative and qualitative MES characteristics is the key factor of a high risk of cardiocerebral embolic complications.