In the treatment of myocardial infarction (MI), secondary prevention administered through cardiac rehabilitation (CR) is an important contributor to mortality reduction (1). Core components of a multidisciplinary CR program are well recognized and should include individual patient assessment, management and control of cardiovascular risk factors, physical activity counselling, prescription of exercise training, dietary advice, psychosocial management, vocational support, and lifestyle behaviour change including patients´ adherence and self-management (2,3). The overall quality of CR services in Sweden and adherence to European standards are high (4,5).

The intervention in the current study is targeting supervised exercise-based cardiac rehabilitation (EBCR), which is described as a central part of a CR-program and has as such been given high priority in international guidelines (6,7). The benefits of center-based EBCR for patients after an MI are robustly shown, in terms of reduced hospital readmissions, cardiovascular mortality and risk of recurrent MI (8), improved aerobic exercise capacity and health-related quality of life (HRQoL) (8,9). In spite of its established positive effects, center-based EBCR remains underused in patients after MI, in Sweden (10) and beyond (11), which limits the effectiveness of the treatment. As lack of adherence to center-based EBCR is associated with an increased risk for recurrent events and increased burden on the healthcare system, there is an urgent need to develop feasible, safe, and evidence-based options and adjuncts to center-based EBCR (12). To increase access, unsupervised home-based EBCR-programs have been suggested (13), but are criticized for lack of supervision, safety issues, as well as difficulties to optimally prescribe and progress exercise.

Barriers related to attendance at center-based EBCR are well described (14) and now include the Covid-19 pandemic which widely caused a temporary closure of center-based EBCR (12). Telerehabilitation means rehabilitation from a distance involving real-time two-way interaction over a digital connection and provides the opportunity to overcome barriers to attendance by combining the accessibility of home-based EBCR programs with specialist monitoring, interaction and support of center-based EBCR (12). Recently published studies have shown that technology acceptance by patients is high (15) and initial evidence suggests that telerehabilitation may be an effective alternative or adjunct to increase aerobic capacity and physical activity behavior after MI (12,16). The most recently published systematic review, including a total of eight studies and 750 patients with coronary artery disease, found similar effects of telerehabilitation and center-based EBCR on aerobic capacity, cardiac risk factors and the physical domain of HRQoL, while effects on total cholesterol and the mental domain of HRQoL were in favor of center-based EBCR (17).

To date, studies investigating effects of telerehabilitation, in terms of remotely delivered EBCR, on recurrent events, rehospitalization and mortality are lacking. Another major limitation is that most previous studies are single center with a small number of patients (16,17). There is also a need for further studies to evaluate the effects of telerehabilitation implementation on participation rates and adherence to EBCR and safety monitoring needs to be more extensively assessed in a real-world setting (12,17).

Therefore, the primary aim of the Remote Exercise SWEDEHEART study is to evaluate if the mean number of completed EBCR sessions differs between intervention centers (offering center-based EBCR, remote EBCR or a combination of both modes) and control centers, offering center-based EBCR, only. The proportion completers in each group will be presented in a supportive responder analysis.

Secondary aims include evaluating safety and feasibility, physical fitness, patient-reported outcome measures (PROMs), cost-effectiveness and follow-up of major adverse cardiovascular events (MACE), including cardiovascular- and all-cause mortality, recurrent hospitalization for acute coronary syndrome, heart failure hospitalization, stroke and coronary revascularization 1 and 3 years after index MI. We hypothesize that remote EBCR, as an alternative to center-based EBCR can increase the participation in EBCR sessions compared to center-based EBCR alone. This will in turn contribute to reduced cardiovascular mortality, rehospitalizations and recurrent MI and will provide a more equal access to EBCR across the country.