“Safety and Efficacy of Exercise-based cardiac rehabilitation in patients with refractory angina: a randomized, controlled trial”

Aim Evidence is scarce regarding safety and anti-ischemic effects of exercise-based cardiac rehabilitation (ECR) in patients with refractory angina (RA).

This was a prospective, single-center, randomized controlled study that assessed a 12-week ECR program in patients with RA. Death and cardiovascular events, anginal symptoms, exercise stress echocardiogram (ESE) and cardiopulmonary exercise test (CPET) parameters were evaluated. When significant differences were detected, Bonferroni post hoc comparisons were conducted.

No difference regarding clinical events and anginal symptoms was found between groups. In ESE, rehab group (RG) increased in peak load (RGpost to RGpre, P = 0.001; interaction, P < 0.001), angina quantification (RGpost to RGpre, P = 0.004; control group (CG)pre than CGpost, P = 0.006; RGpost than CGpre, P = 0.0019; interaction, P = 0.001), exercise duration (RGpost to RGpre, P = 0.009; interaction, P = 0.006), ischemic threshold (RGpost to RGpre, P = 0.001; CGpre than CGpost, P = 0.03; RGpost than CGpre, P = 0.008; interaction, P = 0.005) and angina threshold (RGpost to RGpre, P = 0.04; RGpost than CGpost, P = 0.04; interaction, P = 0.002). In CPET, RG had increased exercise duration and covered distance in RGpost (RGpre than RGpost, P = 0.001; interaction, P = 0.014, RGpre than RGpost, P < 0.001; interaction, P < 0.01; respectively).

A 12-week ECR was safe and promoted positive clinical effects regarding exercise duration, intensity of angina, and angina and ischemic thresholds in RA patients. The trial registry: Cardiac Rehabilitation in Patients with Refractory Angina (NCT03218891) Competing Interest Statement The authors have declared no competing interest. Clinical Trial NCT03218891 Funding Statement This study was supported by Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP, no. 201400345-0). Dr. Carlos Eduardo Negrão was supported by Conselho Nacional de Pesquisa (CNPq, 304697/2020-6). Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The study was approved by the ethics and research committee of the Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (CAAE: 24308213.7.0000.0068) and submitted to and approved by clinical trials.gov (NCT03218891). I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes Data Availability The data that support the findings of this study are available from the corresponding author, LOCD, upon reasonable request.