Muticentre Assessment of Cardiovascular Hemodynamics and Autonomic Dysfunction with Long COVID

The COVID-19 pandemic has had a devastating impact on Canada and worldwide. There are numerous reports of patients suffering from ongoing chronic symptoms, even several months after resolution of the acute illness. These ongoing symptoms have been termed "Long-COVID". Common symptoms among these patients includes exertional dyspnea, fatigue, exercise intolerance, lightheadedness, and tachycardia/palpitation. Long-COVID seems to resemble chronic orthostatic intolerance (COI), in which special nerves called autonomic nerves fail to normally control heart rate and blood pressure. Patients with COI have symptoms on standing such as palpitations, chest pains, dyspnea, tremulousness, and mental clouding that are relieved by lying down,. These symptoms last >3 months (like in Long-COVID) and many start with a viral-like illness. Some specific COI disorders include Postural Tachycardia Syndrome (POTS) Inappropriate Sinus Tachycardia (IST), and Orthostatic Hypotension (OH). Treatments are effective but can be different for each of the COI disorders. We do not know how often autonomic nerves work poorly in Long-COVID, whether it is more common in patients with certain symptoms, and how common the different COI disorders are in Long-COVID. In this national cross-sectional study, we seek to characterize cardiovascular autonomic nerve function in Long-COVID. In Aim#1, we will use sophisticated non-invasive tools to understand the heart rate and blood pressure regulation, symptoms and functional burden, Long-COVID patients. In Aim#2, we will determine how common are autonomic dysfunction disorders in patients with Long-COVID, and if these are associated with specific symptoms. In Aim#3, we will bring patients back at 3 months to get early signals about recovery back to normal. If we can understand the problems underlying Long-COVID across Canada, we can develop specific targeted treatments.