Introduction: syncope (S) is a common manifestation, being the vasovagal (VV) the most common cause. The diagnosis is based on interrogation and reproducibility of S in the tilt test (TT), but it has high incidence of false negatives and time consuming. Since 2008 we have evaluated the utility of measuring the delay of the pulse wave carotid from QRS onset during TT to early predict the outcome in patients (p) with a history of S VV with encouraging results.
Objectives: To analyze the novel parameter for TT in P with S of probable VV compared with a control group without S. Methodology: Prospective observational study in 100 consecutive p S of probable VV and 30 volunteers without S, which was performed by recording conventional TT FC, SBP, DBP and the non-invasive wave of carotid pulse with pressure transducer in multichannel polygraph, measuring the interval from the onset of QRS to the carotid pulse wave by digital caliper accuracy + / - 2 mseg to 100 mm / sec, from baseline to the end of the study (s or 45 '). Capacity was evaluated under 17 sec delay of the pulse wave to predict the outcome of the TT in the first 5 minutes of tilt. Statistically the baseline characteristics of the p of the three groups was compared using Fisher's exact test. To assess predictors of outcome TT univariate models were created and the variables with p less than 0.05 were entered into multivariate model. After verifying the independent association between the delay of the carotid pulse wave and the result of the TT, we constructed COR curves to evaluate the discriminative ability of the parameter and detect threshold value better sensitivity and specificity. The discriminative ability was assessed with the C statistic confidence interval of 95%. Result:There were not any significant differences between the characteristics of the groups with positive or negative TT, or the control group. The only statistically significant parameter associated with the result of the TT was the delay of the carotid pulse wave (greater than 17 mseg) within five minutes of the inclination.

Conclusions: the delay in the pulse wave identified 78% of the S p with history and positive TT and S 2 in the control group developed.