UNLABELLED: The authors have examined 73 patients at the mean age of 36.8 +/- 15.3 (M:34, F:39). All the pts have suffered from recurrent presyncopes or syncopes the etiology of which has not been diagnosed by previous internal, neurological or psychiatric examination. Before the HUT the patients have undergone a complete cardiological examination. The HUT has been carried out according to the modificated Westminster protocol, the blood pressure and the heart rate have been monitored continuously. The end-point of the HUT has been a presyncope or a syncope, viewed as positive. The positive pts have been divided into 4 groups according to the changes of their blood pressure and heart rate during a presyncope or a syncope-mixed, cardioinhibitory A, cardioinhibitory B and vasodepressor responses. Out of 73 pts there have been 27 pts (37%) with positive responses and 46 (63%) with negative responses. The mixed type has been achieved in 12 pts, cardioinhibitory A-in 5 pts, cardioinhibitory B-in 2 pts, vasodepressoric in 8 pts. The mean time needed for positive response during the native HUT has been 17.7 +/- 11 min, after activating with isoproterenol for 2.6 +/- 1 min. The achieved results correlate with data in medical literature. The test activated with isoproterenol increases its sensitivity. There have not been any complications marked within the examined group.

CONCLUSION: The HUT has been unambiguously included into screening algorithms of syncopes as an easy, cheap, safe examination with good sensitivity and specificity.

Keywords: Adult; Blood Pressure; Female; Heart Rate; Humans; Male; Syncope /etiology/; Tilt-Table Test