Post-COVID postural orthostatic tachycardia syndrome: Documentation of a hyperadrenergic phenotype by comprehensive autonomic testing

Postural orthostatic tachycardia syndrome (POTS) is a form of dysautonomia characterized by an excessive increase in heart rate upon standing, in the absence of orthostatic hypotension. Post-infectious forms, particularly following SARS-CoV-2 infection, have been increasingly reported. We report the case of a 34-year-old woman presenting with persistent palpitations, marked fatigue, and orthostatic intolerance that developed two weeks after a mild COVID-19 infection. Standard cardiological evaluation revealed no abnormalities. Comprehensive autonomic testing demonstrated an increase in heart rate from 72 to 109 beats per minute at the 11th minute of active standing (Δ +37 bpm), without significant blood pressure drop, confirming the diagnosis of POTS. Additional autonomic assessment identified a hyperadrenergic phenotype. After two months of treatment with ivabradine (5mg daily), heart rate in the standing position stabilized between 80 and 100 beats per minute, with partial clinical improvement. This case highlights the importance of comprehensive autonomic evaluation in post-COVID forms of POTS and supports the role of targeted therapy.