Heart rate variability follow-up during COVID-19 -a case report.

Background: To detect an early increase in the inflammatory response might prove to be vital for mitigating the deleterious effects of the disease over time.

Cases: A 52-year-old obese man with moderate asthma and hypertension, who developed COVID-19 and had moderate symptoms, used a wearable device to record heart rate variability (HRV) during his illness. He had low parasympathetic tone, which decreased daily until it reached almost 2 standard deviations (SD) below normal values at the end of the second week.