Christiano Gonçalves de Araújo et al. Maria Betânia Solis Resende Julia Teixeira Tupinambás Rebeca Coeli Teodoro Maciel Dias … Flávio Coelho Barros Maria Carmen Melo Vasconcelos José Nelio Januário Antonio Luiz Pinho Ribeiro Maria Carmo P. Nunes
Abstract
Background
Patients with sickle cell disease (SCD) are at increased risk for cardiovascular complications. Exercise testing is used as a prognostic marker in a variety of cardiovascular diseases. However, there is a lack of evidence on exercise in SCD patients, particularly regarding its safety, feasibility, and possible prognostic role.
Objectives
We used the maximal treadmill test to determine safety and feasibility of the exercise testing in SCD patients. Additionally, the factors associated with exercise duration, as well as the impact of exercise-induced changes on clinical outcome, were also assessed.
Methods
One-hundred thirteen patients with SCD, who underwent exercise testing, were prospectively enrolled. A comprehensive cardiovascular evaluation, including echocardiography and B-type natriuretic peptide (BNP) levels, were obtained. The long-term outcome was a composite endpoint of death, severe acute painful episodes, acute chest syndrome, or hospitalization for other SCD-related complications. Cox regression analysis was performed to identify the variables associated with the outcome. A p-value<0.05 was considered to be statistically significant.
Results
The mean age was 36 ± 12 years (range, 18-65 years), and 62 patients were women (52%). Ischemic electrocardiogram and abnormal blood pressure (BP) response to exercise were detected in 17% and 9%, respectively. Two patients experienced pain crises within 48 hours that required hospitalization. Factors associated with exercise duration were age, sex, tricuspid regurgitation (TR) maximal velocity, and E/e’ ratio, after adjustment for markers of disease severity. During the mean follow-up of 10.1 months (ranging from 1.2 to 26), the endpoint was reached in 27 patients (23%). Independent predictors of adverse events were hemoglobin concentration, late transmitral flow velocity (A wave), and BP response to exercise.
Conclusions
Exercise testing in SCD patients who were clinically stable is feasible. Exercise duration was associated with diastolic function and pulmonary artery pressure. Abnormal BP response was an independent predictor of adverse events.