AIMS: To assess the reproducibility of the response to sequential head-up tilt tests. METHODS AND RESULTS: A head-up tilt test was performed early after syncope in 127 patients with a normal ECG and no structural heart disease. Patients with a positive response (82 patients) were randomized to two (1 week and 2 weeks later) or one (2 weeks later) additional head-up tilt tests, and patients with a negative response (45 patients) were randomized to a second head-up tilt test 1 or 2 weeks after the first. The reproducibility of a positive response in the second head-up tilt test was 80% after 1 week and 53% after 2 weeks (P<0.01). Only 53% of the patients with a positive response to a first and second head-up tilt test had a positive response to a third (P=0.01). Intra-individual variation in the time to a positive response was wide. The reproducibility of the cardioinhibitory responses was very poor. Reproducibility of a negative response was 80%. CONCLUSIONS: In patients with recent syncope, the rate of positive responses decreases with sequential head-up tilt tests. Furthermore, the time to a positive response in different head-up tilt tests shows important intra-individual variations, and the reproducibility of the cardioinhibitory responses is very poor. In contrast, the reproducibility of the negative responses is high. Copyright 2002 The European Society of Cardiology. Published by Elsevier Science Ltd. All rights reserved
RCT Entities:
AIMS: To assess the reproducibility of the response to sequential head-up tilt tests. METHODS AND RESULTS: A head-up tilt test was performed early after syncope in 127 patients with a normal ECG and no structural heart disease. Patients with a positive response (82 patients) were randomized to two (1 week and 2 weeks later) or one (2 weeks later) additional head-up tilt tests, and patients with a negative response (45 patients) were randomized to a second head-up tilt test 1 or 2 weeks after the first. The reproducibility of a positive response in the second head-up tilt test was 80% after 1 week and 53% after 2 weeks (P<0.01). Only 53% of the patients with a positive response to a first and second head-up tilt test had a positive response to a third (P=0.01). Intra-individual variation in the time to a positive response was wide. The reproducibility of the cardioinhibitory responses was very poor. Reproducibility of a negative response was 80%. CONCLUSIONS: In patients with recent syncope, the rate of positive responses decreases with sequential head-up tilt tests. Furthermore, the time to a positive response in different head-up tilt tests shows important intra-individual variations, and the reproducibility of the cardioinhibitory responses is very poor. In contrast, the reproducibility of the negative responses is high. Copyright 2002 The European Society of Cardiology. Published by Elsevier Science Ltd. All rights reserved