Physiological, biological and genetic abnormalitities associated with the postural tachycardia syndrome

体位性站立性心动过速综合征（POTS）是一种临床综合征，其特征是在直立体位时出现过速（心率每分钟增加30次或更多）。这种情况伴随着虚弱、头晕、晕厥前期或昏厥。POTS直到最近才引起国际医学界的关注，因为患有这种疾病的患者数量正在稳步上升。POTS的症状和持续的残疾似乎主要是由站立时的超常反射交感神经激活引起的，其方式在某些症状中很明显，如心动过速，但在其他症状中则不明显，如没有体位性低血压时的体位性晕厥。不明确的诊断标准和多种病因的可能性使得很难阐明POTS的潜在病理生理。在这个项目中，我将研究POTS患者的交感神经系统对直立倾斜的反应，以及可能支持该综合征的遗传和表观遗传机制。初步结果令人鼓舞，值得进一步研究。

Postural Orthostatic Tachycardia Syndrome (POTS) is a clinical syndrome characterized by the development of excessive tachycardia (heart rate increases by 30 beats or more per min) when the upright position is assumed. The condition is accompanied by weakness, dizziness, presyncope or fainting. POTS has only recently come to international medical attention as the number of patients with the condition is steadily rising. The symptoms and ongoing disability in POTS appear to primarily result from a supernormal reflex sympathetic activation on standing, in ways which are readily apparent for some symptoms, such as tachycardia, but obscure for others, such as postural syncope in the absence of postural hypotension. Poorly defined diagnostic criteria and the likelihood of multiple causes have made it difficult to clarify the underlying pathophysiology of POTS. In this project I will investigate the sympathetic nervous system response to head-up tilt in patients with POTS as well as possible genetic and epigenetic mechanisms which might underpin the syndrome. Preliminary results are encouraging and merit to be taken further.