Tilt testing and what you should know about it - Experience with 835 consecutive patients with syncope of unknown origin

Abstract

BackgroundNumerous tilt testing protocols with and without a preceding passive phase or the administration of nitrates have already been investigated. However, a truely standardized method for the investigation does not yet exist. Methods and resultsA total of 835 consecutive patients who underwent tilt testing between January 2005 and March 2015 were included in this study. Results of a passive tilt test (PTT), a nitrate-stimulated tilt test (NSTT) with a preceding passive phase of 20 min, or an early nitrate-stimulated tilt test (ENSTT) without a preceding passive phase were compared and analyzed retrospectively in 735 patients. In addition, a further 100 consecutive patients were prospectively randomized 1:1 to compare NSTT and ENSTT. In the retrospective analysis, 38% of the patients in the ENSTT group had a positive test response compared with 45% in the NSTT group and only 27% in the PTT group (p = 0.0002). In the prospective study, 34% of the patients had a positive test response in the ENSTT group compared with 42% in the NSTT group (p = 0.537). The mean duration to a positive test response was significantly shorter in the ENSTT group (retrospective and prospective p < 0.001). The nitrate-stimulated groups did not differ significantly with respect to the hemodynamic characteristics of a positive test response (retrospective: p = 0.773; prospective: p = 0.086). ConclusionDue to the rate of positive test response being comparable to other protocols and its significantly shorter test duration, nitrate-stimulated tilt testing without a preceding passive tilt test may be favored for use in a busy clinical practice.