Eight Weeks of Supervised Pulmonary Rehabilitation Are Effective in Improving Resting Heart Rate and Heart Rate Recovery in Severe COVID-19 Patient Survivors of Mechanical Ventilation

Background and Objectives: Patients who survive severe COVID-19 require significant pulmonary rehabilitation. Heart rate (HR) has been used as a safety variable in the evaluation of the results of interventions in patients undergoing pulmonary rehabilitation. The aim of this research was to analyse HR during a pulmonary rehabilitation program in post-severe COVID-19 patients who survived mechanical ventilation (MV). The study includes the initial and final evaluations and aerobic training sessions. Materials and Methods: Twenty patients (58 ± 13 years, 11 men) were trained for 8 weeks. A 6-minute walk test (6 MWT) was performed and, subsequently, a supervised and individualised training plan was created. Resting heart rate (RHR), heart rate recovery (HRR), heart rate at minute 6 (HR6 min) and the product of HR6 min and systolic blood pressure (HR6 min^xSBP) were measured at 6 MWT. In addition, HR was measured at each training session. Results: After 8 weeks of pulmonary rehabilitation, patients decreased their RHR from 81.95 ± 9.36 to 73.60 ± 9.82 beats/min (p < 0.001) and significantly increased their HRR from 12.45 ± 10.22 to 20.55 ± 7.33 beats/min (p = 0.005). HR6 min presented a significant relationship with walking speed and walked distance after the pulmonary rehabilitation period (r = 0.555, p = 0.011 and r = 0.613, p = 0.011, respectively). HR6 min^xSBP presented a significant relationship with walking speed and walked distance after training (r = 0.538, p = 0.014 and r = 0.568, p = 0.008, respectively). In the pulmonary rehabilitation sessions, a significant decrease in HR was observed at minutes 1, 6 and 15 (p < 0.05) between sessions 1 and 6 and at minute 1 between sessions 1 and 12. Conclusions: Eight weeks of individualised and supervised pulmonary rehabilitation were effective in improving RHR and HRR in COVID-19 patients surviving MV. HR is an easily accessible indicator that could help to monitor the evaluation and development of a pulmonary rehabilitation program in COVID-19 patients who survived MV.