Grubb B P, Kosinski D J, Boehm K, Kip K
Department of Medicine, Medical College of Ohio, Toledo 43699, USA.
Pacing Clin Electrophysiol. 1997 Sep;20(9 Pt 1):2205-12. doi: 10.1111/j.1540-8159.1997.tb04238.x.
Head upright tilt table testing has emerged as an accepted modality for identifying an individual's predisposition to episodes of autonomically mediated hypotension and bradycardia that are sufficiently profound so that transient loss of consciousness ensues (neurocardiogenic syncope). However it has also become apparent that less dramatic falls in blood pressure, while not sufficient to cause full syncope, may produce symptoms such as near syncope, vertigo, dizziness, and TIA-like episodes. We have identified a subgroup of individuals with a mild form of autonomic dysfunction with symptoms of postural tachycardia and lightheadedness, disabling fatigue, exercise intolerance, dizziness, and near syncope. During baseline tilt table testing these patients demonstrated a heart rate increase of > or = 30 beats/min (or a maximum heart rate of 120 beats/min) within the first 10 minutes upright (unassociated with profound hypotension), which reproduced their symptom complex. In addition these patients exhibit an exaggerated response to isoproterenol infusions. Similar observations have been made by others who have dubbed this entity the Postural Orthostatic Tachycardia Syndrome (POTS). We conclude that POTS represents a mild (and potentially treatable) from of autonomic dysfunction that can be readily diagnosed during head upright tilt table testing.
头部直立倾斜试验已成为一种公认的方法，用于确定个体是否易发生由自主神经介导的严重低血压和心动过缓发作，这种发作严重到足以导致意识短暂丧失（神经心源性晕厥）。然而，也已明显发现，血压较轻微下降虽然不足以引起完全晕厥，但可能产生诸如接近晕厥、眩晕、头晕和短暂性脑缺血发作样发作等症状。我们已经确定了一组患有轻度自主神经功能障碍的个体，他们有体位性心动过速和头晕、致残性疲劳、运动不耐受、头晕及接近晕厥等症状。在基线倾斜试验期间，这些患者在直立的最初10分钟内心率增加≥30次/分钟（或最大心率为120次/分钟）（与严重低血压无关），这重现了他们的症状复合体。此外，这些患者对异丙肾上腺素输注表现出过度反应。其他人也有类似观察结果，他们将这个实体称为体位性直立性心动过速综合征（POTS）。我们得出结论，POTS代表一种轻度（且可能可治疗）的自主神经功能障碍形式，可在头部直立倾斜试验期间轻易诊断出来。
