Heart Rate Variability And Cardio-Renal Outcomes In Patients With Novel Covid 19 Infection

ABSTRACT

Studies have shown that SARS-CoV2 can infect the vagal nerve and its connections to the brain stem. This neuronal involvement is seen mostly in the delayed inflammatory phase. It is associated with autonomic nervous system dysfunction, resulting in decreased respiratory ventilation and impaired blood pressure as well as heart rate regulation. The dysautonomia seen in SARSCoV-2 infection can be measured, and heart rate variability (HRV) measurement is one method. Our study explores the relationship between autonomic dysfunction and mortality in patients with COVID- 19 using HRV measurement. In a prospective design, data of consecutive patients with SARS-CoV-2 positive infection admitted to Banner university of Arizona, Tucson, and whose telemetry information was available was collected between August 2020 to November 2021. We attempted to use the telemetry data to measure diurnal heart rate variation by obtaining mean average hourly heart rates, divided into 12-hour day/night periods. The primary outcome measure was mortality. The secondary outcome measured includes incidence of acute kidney injury, transfer to ICU, need for mechanical ventilation, and live discharge from hospital. 334 patients were included in the study. The baseline demographic characteristics, medical history, radiological data, laboratory data, details of medications, and hospital course were reported. Diseases associated with an autonomic dysfunction like diabetes mellitus, chronic renal failure, a history of alcohol abuse, clinical evidence of autonomic neuropathy, or a recent myocardial infarction, documented constrictive or hypertrophic cardiomyopathy, sustained non-sinus dysrhythmias, atrioventricular conduction defects will be excluded in the final analysis. Mortality was high in patients with lower heart rate variability. Compared with survivors, non-survivors were older, were less frequently women, had a higher prevalence of diabetes mellitus, longer stay in the hospital, received an organ transplant, smoking, and higher level of calcitonin. Lower heart rate variability was associated with a higher incidence of acute kidney injury, need for mechanical ventilation, and need for ECMO. This study suggests that analysis of the variability of heart rate may have prognostic implications in patients with COVID19.