Long-Haul Post–COVID-19 Symptoms Presenting as a Variant of Postural Orthostatic Tachycardia Syndrome oleh Madeleine Johansson, MD, PhD, Marcus Ståhlberg, MD, PhD, Michael Runold, MD, PhD, Malin Nygren-Bonnier, PhD, PT, Jan Nilsson, MD, PhD, Brian Olshansky, MD, Judith Bruchfeld, MD, PhD, Artur Fedorowski, MD, PhD