Postural Tachycardia Syndrome (PoTS) is a chronic condition often affecting multiple systems with varied presenting symptoms. Diagnosis is made by demonstrating cardiovascular criteria on standing along with clinical assessment. Cardiopulmonary exercise testing has been used to demonstrate and characterise the physiological response to exercise and the severity of the syndrome. Previous studies on exercise testing in these patients have focussed on cardiovascular changes alone. This series characterises the integrated cardiac and respiratory response to exercise seen with cardiopulmonary exercise testing. Our main findings show that peak oxygen uptake, work done and peak heart rate are significantly reduced from their respective predicted values in PoTS patients. However, despite this, most patients demonstrated a normal exercise capacity. Features of ventilatory inefficiency were also seen which suggest exercise capacity in these patients may be limited more by impaired ventilatory control such as dysfunctional breathing during exercise rather than by cardiovascular issues.

中文翻译：

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描述姿势性心动过速综合征 (PoTS) 心肺运动测试特征的观察性病例系列

姿势性心动过速综合征 (PoTS) 是一种慢性疾病，通常会影响多个系统，并具有不同的表现症状。诊断是通过证明心血管标准与临床评估一起进行的。心肺运动测试已被用于证明和表征对运动的生理反应和综合征的严重程度。以前对这些患者进行运动测试的研究仅关注心血管变化。该系列描述了心肺运动测试中对运动的综合心脏和呼吸反应。我们的主要发现表明，在 PoTS 患者中，峰值摄氧量、完成的功和峰值心率与其各自的预测值相比显着降低。然而，尽管如此，大多数患者表现出正常的运动能力。