Protocol update for a randomised controlled feasibility trial of exercise rehabilitation for people with postural tachycardia syndrome: the PULSE study oleh Gordon McGregor, Becky Evans, Harbinder Sandhu, Jane Simmonds, Shivam Joshi, Gita Devi, Albiona Zhupaj, Nikki Holliday, Gemma Pearce, Chloe Patel, Siew Wan Hee, Richard Powell, Peter Heine, Shilpa Patel, Lesley Kavi, Julie Bruce, Sajad Hayat, Boon Lim, Helen Eftekhari, Sandeep Panikker