Evaluation of Heart Rate Recovery Index in Patients with Coronavirus Disease

Objectives: In coronavirus disease-2019 (COVID-19), autonomic dysfunction may ensue. The heart rate recovery index (HRRI) measures autonomic function and predicts cardiovascular disease (CVD). The research assessed HRRI in patients with COVID-19. Materials and Methods: The research group included 160 verified COVID-19 cases, and the control group had 160 healthy participants without a history of immunization. All patients underwent treadmill stress electrocardiogram according to the Bruce protocol. After the stress test, HRRIs were taken at 1, 2, 3, and 5 min. HRRI is computed by subtracting the subject’s maximum exercise heart rate (HR) at the end of the exercise from HR after 1, 2, 3, and 5 min of recovery. Results: Both groups had equal exercise duration, metabolic equivalents, maximum (max.) HR, systolic blood pressure (SBP) and diastolic blood pressure (DBP) at baseline, max. SBP and DBP, and changes in SBP and DBP (p>0.05). HRRIs were greater in COVID-19 patients than in controls at 1, 2, 3, and 5 min (p