Recuperação da frequência cardíaca após o teste de caminhada de 6 minutos em pacientes com insuficiência cardíaca

Abstract

Introduction: In Heart Failure (HF), a functional test used to predict the prognosis is the 6-minute Walk Test (6MWT), where distances below 300m lead to a worse prognosis. Another measurement that also has prognostic value is heart rate (HR), where the slow deceleration of beats during heart rate recovery (HRR), after exercise, indicates an increase in the mortality rate. Objective: to analyze the recovery of heart rate after the 6MWT and verify the relationship between HRR and the clinical outcomes of hospitalization, physical exercise, medication use and death in individuals with HF and to verify the correlation between HRR after the 6MWT and the travelled distance. Methods: This is an observational, longitudinal, prospective study on patients with HF, approved by the research ethics committee under the opinion of CEP no. 6,066,757, recruited from the cardiology outpatient clinic of the Walter Cantídio University Hospital, during the period July 2021 to October 2023. The sample was composed of individuals over the age of 18, male and female, who undergo outpatient follow-up due to HF. Results: 210 patients were evaluated, 102 of whom were male (49%) with a BMI of 28.6±5.3kg/m2 and a mean ventricular ejection fraction of 49±16%. When analyzing the recovery of HR after the 6MWT, only 39 participants achieved a reduction in HR greater than 12 seconds, covering an average distance of 377 ± 104m, leaving the 171 individuals with a HRR of less than or equal to 12 seconds with an average distance of 372 ± 105m, not being statistically significant (p= 0.537). Furthermore, when the relationship between HRR and clinical outcomes was verified, it was observed that none of the outcomes were related to HR recovery. Conclusion: No relationship was observed between heart rate recovery and the distance covered in the 6MWT, and the clinical outcomes analyzed.