Determining the prevalence of Postural Orthostatic Tachycardia Syndrome (POTS) in patients attending the emergency department (ED) with orthostatic symptoms.

This project aims to identify the prevalence of Postural Orthostatic Tachycardia Syndrome (POTS) in patients who attend the emergency department with symptoms consistent with this condition, using a novel diagnostic pathway. Eligible participants will be identified via review of relevant Internal Classification of Diseases (ICD) coding, as determined to be appropriate by the research team. The MALMO POTS questionnaire is a self-assessment symptom score that was developed in 2022. It is based on self-reported severity of twelve commonly reported POTS symptoms including five cardiac and seven non-cardiac symptoms. It has been validated as a useful screening tool for POTS, with a score of 42 or greater yielding 97% sensitivity and 98% specificity for the presence of POTS compared to a normative population. Patients will be invited to participate in the study following review of emergency department discharge paperwork by the research team. Patients will be invited via post in collaboration with their clinical treating team, and if happy to receive further information, consent and completion of the survey will be done via electronic link to a REDCap database. The survey will take approximately 5- 10 minutes to complete. For participants who score 42 or greater in the questionnaire, they will progress to the second stage of the study; formal objective autonomic testing to quantify the presence of POTS. This will require attendance at a private clinic, with testing conducted by clinical nurses and research officers. Testing will include a 12-lead ECG, sudomotor function testing with the SUDOSCAN equipment, and autonomic testing with The Finapres Nova, including Ten-minute Active Stand Test using beat to beat hemodynamic monitoring, the Valsalva manoeuvre, a deep breathing test, and a baroreceptor sensitivity test. The clinic visit will take approximately 30- 60 minutes. Baseline demographics, medical history and medications use will also be collected. Testing will be completed within 6-months of emergency presentation. For participants who meet the criteria for POTS based on the Active Stand Test, results of autonomic testing will be forwarded to their General Practitioner (GP) to allow for appropriate follow up.