Title: Postural Tachycardia Syndrome
题目：体位性心动过速综合征
Author 作者: Semhar Tewelde

1. Postural tachycardia syndrome (POTS) is defined as orthostatic intolerance w/ an increase in heart rate by 30 bpm (or HR>120 bpm) that occurs within 10 mins of standing or upright tilt
体位性心动过速综合征（POTS）被定义为体位不耐受伴立位时心率增加30次（或HR>120次），发生在站立或直立倾斜10分钟内

2. Orthostatic intolerance due to POTS will NOT cause orthostatic hypotension (defined as fall of >20/10 mm Hg on standing); instead patients may display no change, a small decline, or even a modest increase in blood pressure
•由于POTS所造成的体位不耐受将不引起体位性低血压（定义为站立时出现>20/10毫米汞柱的血压下降），反而患者的血压可能会表现没有变化，一个小的下降，甚至可能会升高

3. Symptoms include: palpitations, fatigue, lightheadedness, exercise intolerance, nausea, diminished concentration, tremulousness, and syncope
症状包括：心悸，乏力，头晕，运动耐受力下降，恶心，注意力不集中，震颤，和晕厥

4. POTS is a heterogeneous group of disorders with similar clinical manifestations  
POTS是一组有相似临床表现的不同性质疾病群

a. Primary POTS - partial dysautonomia form
原发性POTS - 部分自律神经失调的形式
b. Secondary POTS - hyperadrenergic form
继发POTS - 高肾上腺素形式

5. Tx varies according to the subtype/etiology of POTS and must be individualized
治疗主要是根据POTS的不同亚型/病因，必须个体化

*Caveat: inappropriate sinus tachycardia (IST) and POTS are two different diagnosis where significant overlap exists, however the tachycardia in IST is NOT postural 
 *要注意：不典型的窦性心动过速（IST）和POTS是两个不同的诊断，存在明显的重叠，但是IST的心动过速并不因体位而变化
 
References 参考文献：Grubb B. Postural Tachycardia Syndrome. Circulation 2008; 117:2814-2817