There is currently no case definition for Long COVID which appears to manifest in a variety of ways in different patients. The frequent issues are of overwhelming fatigue and fogging, intolerance of postural change/being upright and often severely diminished exercise tolerance. Some patients have developed PoTS after COVID and some have had symptoms even after vaccination.
Importantly a number of features of Long COVID appear to be indicative of significant autonomic nervous system dysfunction and it is well recognised that many viruses, including Coronavirus as well as Epstein Barr [glandular fever] virus, and other infectious agents (e.g., Borrelia causing Lyme disease) are capable of profoundly disabling autonomic nervous system function leaving some patients very symptomatic for prolonged periods.
Prof Lobo has developed extensive experience of patients with Long COVID and uses cardiovascular autonomic function testing to characterise the dysautonomia which provides both proof of autonomic dysfunction as well as guiding treatment. This facilitates interventions with novel drug therapies and improvement in patient well-being. For many patients, providing objective evidence of autonomic dysfunction has proven to be very helpful particularly when conventional cardiology and respiratory investigations have not disclosed the cause of their symptoms.