[Efficiency of heart rate and heart rate difference at different time points during head-up tilt test in the diagnosis of postural tachycardia syndrome in children and adolescents].

Objective: To study the efficiency of heart rate (HR) and heart rate difference (HRD) at different time points during head-up tilt test (HUTT) in the diagnosis of postural tachycardia syndrome (POTS) in children and adolescents.

Methods: A total of 217 children and adolescents, aged 6-16 years, who were diagnosed with POTS were enrolled as the POTS group, and 73 healthy children and adolescents, matched for sex and age, were enrolled as the control group. The POTS group was further divided into ≤12 years old group with 127 children/adolescents and >12 years old group with 90 children/adolescents.

[Research advances in cardiovascular system damage caused by SARS-CoV-2 in children].

The outbreak of coronavirus disease 2019 (COVID-19) started in December 2019 in China and the epidemic is still going on at present. Since children are the susceptible population, the number of cases is gradually increasing. In addition to the typical respiratory symptoms, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection also has the clinical symptoms of cardiovascular system damage.