Laser Doppler method in evaluation of vasovagal syncope induced by tilt table test

The laser Doppler flowmetry offers a new noninvasive, real-time technique for monitoring of the blood perfusion in living tissue. In spite of some instrumental problems, e.g. relative calibration and unknown sampling measurement depth, this method has already been used in clinical examination. The purpose of presented study was the application of the laser Doppler method in evaluation of the vasovagal syncope induced in the tilt-table test. Twelve patients with the history of syncopal episodes were examined using the head-up tilt-table test. In the some condition three normal subjects were also examined as the reference. Results of examination have showed that the changes measured by laser Doppler method are clearly visible during the pre-syncope and syncope period. These changes in perfusion precede the subjective clinical symptoms as well as decrease in the blood pressure, blood oxygen saturation and heart rate.