The significance of the ultrasound diagnostics in evaluation of the emboligenic pathogenesis of transient ischemic attacks.

The objective of this study was to examine the possibilities of ultrasound diagnostics in the evaluation of emboligenic pathogenesis of transient ischemic attacks (TIAs) and the frequency of specific origins of embolism. A total of 150 adult patients with TIA and 50 control patients, were examined by neurosonologic, echocardiographic and venous ultrasound examination. Emboligenic pathogenesis of TIA was established in 36.6% of patients. Microembolic signals were detected in 22.7% of the whole group, and 61.8% in emboligenic TIA subgroup. Artery-to-artery embolism from ulcerated plaque of the carotid arteries was found in 12.6% of patients, from the aortic arch atheroma in 3.3% and cardioembolism in 12.6% (atrial fibrillation 7.3%, atrial septal aneurysm 2%, mitral valve prolapse 2%, mechanical heart valve 0.7%, left atrium thrombus 0.7%). Paradoxic embolism with the patent foramen ovale was established in 6% of patients, and with the pulmonary right-to-left shunt in 2%. Correlation with controls showed significantly higher frequency of the ulcerated carotid plaque and frequency of microembolic signals in the TIA group (p < 0.05). The patients with potential sources of embolism had a greater risk of developing TIA than those without these sources.