Vnitr Lek 2005, 51(11):1272-1276

The influence of the passive phase shortening on the diagnostic yield of nitroglycerine stimulated head-up tilt test

P. Mitro^*, M. Szakács

III. interná klinika Lekárskej fakulty UPJŠ a FN L. Pasteura, Košice, Slovenská republika, prednosta doc. MUDr. Peter Mitro, Ph.D.

The aim of the study was to compare the diagnostic yield of three different head-up tilt test protocols. A total of 438 patients with syncope of unexplained etiology were examined. Protocol I was represented by Westminster protocol (passive test for 45 minutes, 60) followed, if negative, by nitroglycerine (NTG) stimulated test for another 15 minutes. Protocol I was performed in 236 patients (99 men, 137 women, mean age 37.7 ± 18.9 years). In protocol II, passive phase was shortened to 30 minutes followed by 15 minutes NTG stimulated test. It was performed in 116 patients (38 men, 78 women, mean age 35.7 ± 18.9 years). Protocol III - Italian protocol - consisted of 20 minutes passive phase and 15 minutes NTG stimulated phase and was performed in 86 patients (25 men, 61 women, mean age 38.2 ± 18.1 years). The positivity rate of passive phase declines with the shortening of passive phase from 45 minutes to 30 minutes and 20 minutes respectively (21 % vs 9 % vs 18 %, p = 0,04) and it raises in NTG stimulated phase reciprocally (79 % vs 91 % vs 82 %, p = 0.04). The total positivity rate is not significantly different in three protocols (63 % vs 70 % vs 71 %, p = 0.81). Frequency of mixed type vasovagal syncope is decreasing (63 % vs 54 % vs 41 %, p = 0.004) and frequency of vasodepressor type is increasing (24 % vs 38 % vs 54 %, p = 0.003) by the shortening of passive phase of head-up tilt test. The frequency of cardioinhibitory type is the same. Duration of NTG stimulated phase is not different in three different protocols (6.8 ± 4.1 min vs 6.0 ± 4.1 min vs 5.4 ± 3.1 min, p = 0.16). Thus, the passive phase shortening of NTG stimulated head-up tilt test does not decrease the diagnostic yield of the test and has an advantage of time saving in this time consuming procedure.

Keywords: head-up tilt test; nitroglycerine; vasovagal syncope; diagnosis

Received: October 8, 2004; Accepted: April 29, 2005; Published: November 1, 2005  Show citation