Traditional versus extended hybrid cardiac rehabilitation based on the continuous care model for coronary artery bypass surgery patients in a middle-income country: an embedded mixed method
Authors: Pakrad F , Ahmadi F , Grace S , Oshvandi K , Kazemnejad A 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Cardiac rehabilitation (CR) is a proven method to reduce the risk of disease, but unfortunately in low-and middle-income countries (LMICs), it is either unavailable or done in small quantities.

Purpose
To compare traditional (1-month supervised) vs hybrid cardiac rehabilitation (CR; usual care) with an additional 3 months offered remotely based on the continuous care model (intervention) in patients who have undergone coronary artery bypass graft (CABG).

Methods
The embedded method has been used for the conduction of this study in two phases. The first phase of the study was carried out using a randomised clinical trial. Of 107 eligible patients who were referred to CR during the period of study, 82.2% (N=88) were enrolled (target sample size). Participants were randomly assigned 1:1 (concealed; 44 per parallel arm). After CR, participants were given a mobile application and communicated biweekly with the nurse from months 1-4 to control risk factors. Quality of life (QOL, Short Form-36, primary outcome); functional capacity (treadmill test); and the Depression, Anxiety and Stress Scale were evaluated pre-CR, after 1 month, and 3 months after CR (end of intervention), as well as re-hospitalisation. In the second phase, a qualitative study was conducted using the conventional content analysis method. 17 patients from the intervention group and 3 members of their families were interviewed.

Results
The results of the quantitative stage showed the analysis of variance interaction effects for the physical and mental component summary scores of QOL were &lt;.001, favoring intervention (per protocol); there were also significant increases from pre-CR to 1 month, and from 1 month to the final assessment in the intervention arm (P&lt;.001), with change in the control arm only to 1 month. The effect sizes were 0.115 and 0.248, respectively. Similarly, the interaction effect for functional capacity was significant (P&lt;.001), with a clinically significant 1.5 metabolic equivalent of task increase in the intervention arm. There were trends for group effects for the psychosocial indicators, with paired t tests revealing significant increases in each at both assessment points in the intervention arm. At 4 months, there were 4 (10.3%) re-hospitalisations in the control arm and none in intervention (P=.049). Intended theoretical mechanisms were also affected by the intervention. From the analysis of qualitative data, 20 subcategories, 6 categories, and three themes, including promotion and continuity of self-care, self-efficacy enhancement, belief, and lifestyle modification were extracted. Finally, qualitative findings supported quantitative findings.

Conclusions
Extending CR in this accessible manner, rendering it more comprehensive was effective in improving outcomes. Therefore, using the CCM can greatly reduce the gap due to cardiac rehabilitation in LMICs.