Abstract 12824: Quantitative Autonomic Testing ‘Early’ and ‘Late’ After Recovery From Acute COVID-19 Illness

Abstract

Background: Cardiovascular (CV) autonomic dysfunction (AD) is a known potential complication following acute COVID-19 illness and may contribute to persistent symptoms, such as fatigue and postural intolerance. However, the quantitative assessment of CV AD after an acute COVID-19 infection is largely unexplored. Objective: Compare CV autonomic testing in patients presenting ‘early’ and ‘late’ after an acute COVID-19 illness. Methods: CV autonomic testing was undertaken in symptomatic patients presenting ‘early’ (0-10 months) and ‘late’ (11-20 months) after an acute COVID-19 illness. Findings were compared to autonomic testing results in healthy control subjects. Measures included i) heart rate (HR) and blood pressure (BP) responses during active standing (AS), ii) time to BP nadir and recovery during AS, iii) Valsalva ratio (VR), and iv) respiratory sinus arrhythmia (RSA). Unpaired student t-test was used to compare findings (mean ± SD) in post-COVID patients to controls. A p-value of <0.05 was statistically significant. Results: Control (n=82, mean 33 years, 87% female), ‘early’ (n= 37, mean 38 years, 89% female) and ‘late’(n=18, mean 43 years, 72% female) groups were similar in age and sex. Compared to controls, VR was abnormally low in both the ‘early’ and ‘late’ groups (‘early’ 1.5 and ‘late’ 1.4 vs. controls 1.7, both p<0.03) ( Table ). Other autonomic measures did not differ significantly from controls. However, compared to the ’early’ group, the ‘late’ group exhibited a trend toward more marked AD ( Figure ). Conclusion: Patients presenting ‘early’ and ‘late’ after an acute COVID-19 illness exhibit similar severity of autonomic disturbance. Potentially, the ‘late’ group experienced more severe COVID illness leading to delayed referral for troublesome AD symptoms. Nonetheless, our findings suggest that abnormal CV AD findings may persist without apparent improvement for lengthy periods (up to 20 months in this study) after acute COVID-19 infection.