Cardiac Function Test Center, Peking Union Medical College and Chinese Academy of Medical Sciences, 167 North Lishi Road, Xicheng State, Beijing, 100037 China.
Europace. 2011 Apr;13(4):576-80. doi: 10.1093/europace/eur015. Epub 2011 Feb 25.
To investigate the appropriate duration of head-up tilt test (HUTT) needed to induce a positive reaction in patients with suspected vasovagal syncope.
Consecutive patients referred to the syncope unit of our centre for recurrent unexplained syncope were studied. The HUTT included a 30 min passive basic phase and a 20 min sublingual nitroglycerin provocation phase if syncope did not develop during the passive phase. We studied 773 consecutive patients, and 427 (55.2%) patients had a positive HUTT, including 46 patients (10.8%) during the passive basic phase and 381 patients (89.2%) during the nitroglycerin provocation phase. During the basic phase, positive reaction appeared at 7.5 min, and the percentage of positive cases increased with the duration of the test, reaching a peak (20.9%) at 22.5 min, and then decreasing gradually. Most positive reactions (96.1%) occurred between 10 and 25 min during the basic phase. During the nitroglycerin provocation phase, however, the percentage of positive reactions increased rapidly after sublingual nitroglycerin, peaking (35.7%) at 10 min, followed by a sharp decline. Most positive reactions (96.1%) occurred in the first 15 min of the provocation phase.
The HUTT was a useful diagnostic test in patients with suspected vasovagal syncope, and sublingual nitroglycerin increased the rate of positive reactions. The appropriate duration for HUTT required at least 25 min during the passive basic phase and 15 min during the nitroglycerin provocation phase.
探讨疑诊血管迷走性晕厥患者行直立倾斜试验（HUTT）诱发阳性反应的适宜时间。
连续入组至本中心因不明原因反复晕厥就诊的患者。HUTT 包括 30 分钟被动基础期和 20 分钟舌下含服硝酸甘油激发期，如果被动期未发生晕厥。共研究了 773 例连续患者，427 例（55.2%）患者 HUTT 阳性，其中 46 例（10.8%）在被动基础期，381 例（89.2%）在硝酸甘油激发期。在基础期，阳性反应出现在第 7.5 分钟，阳性病例比例随试验时间延长而增加，在 22.5 分钟时达到高峰（20.9%），然后逐渐下降。大多数阳性反应（96.1%）发生在基础期的 10-25 分钟之间。然而，在硝酸甘油激发期，舌下含服硝酸甘油后阳性反应比例迅速增加，在 10 分钟时达到高峰（35.7%），随后急剧下降。大多数阳性反应（96.1%）发生在激发期的前 15 分钟内。
HUTT 是疑诊血管迷走性晕厥患者的有用诊断性检查，舌下含服硝酸甘油可提高阳性反应率。HUTT 的适宜持续时间在被动基础期至少需要 25 分钟，在硝酸甘油激发期至少需要 15 分钟。
