Early Versus Standard Access Cardiac Rehabilitation to Counter Ventricular Remodeling Post-MI (EVADE)

BACKGROUND: Cardiac rehabilitation (CR) is an outpatient chronic disease management program delivering secondary prevention, which is proven to reduce morbidity and mortality. The Canadian Cardiovascular Society Access to Care working group recommends patients access CR "preferably" within 2-7 days following percutaneous intervention for myocardial infarction (MI), but that 30-60 days is "acceptable". Despite these benchmarks, in practice patients access CR up to 90 days post-treatment in Canada. This is disconcerting given the detrimental impacts of delayed access to CR. These include ventricular remodeling (i.e., ventricular enlargement and reduced pump function), lower CR use, less post-CR exercise, among others. Accordingly, EVADE will be the first randomized controlled trial (RCT) to test the effects of early access CR (1-week post-discharge to first CR visit) compared to standard access CR (7-weeks post-discharge to first CR visit) in ameliorating these concerns.

AIMS \& HYPOTHESIS: The primary aim is to compare ventricular remodeling as defined by the change in end-systolic volume at 1-year in participants randomized to early versus standard access CR. The secondary aims are: (1) to compare post-CR exercise adherence by accelerometry, exercise capacity by 6-minute walk test distance, and health-related quality of life (HRQL) at 1-year in participants randomized to early versus standard access CR; (2) to compare CR program session attendance in participants randomized to early versus standard access CR; and (3) to assess biomarkers of ventricular remodeling in participants randomized to early versus standard access CR.

The final aims are to explore more immediate health benefits associated with early versus standard access CR. Accordingly, at 6 months following hospital discharge the investigators will measure end-systolic volume, exercise adherence, exercise capacity, biomarkers of ventricular remodeling, and HRQL. The investigators will also explore hospitalization for any cause of death at 1 year in order to inform future research.

The overall hypothesis is that early access CR will be associated with less ventricular remodeling, increased CR attendance and post-CR exercise adherence, increased exercise capacity, and greater HRQL.

DESIGN: EVADE will be a two-centre, 2 parallel-arm, single-blinded RCT. Participants will be recruited through coronary care units following treatment for MI from the Royal University Hospital in Saskatoon, Saskatchewan and the University of Alberta Hospital in Edmonton. The University of Alberta Research Electronic Data Capture (REDCap) online database will randomize (1:1) participants (allocation concealed). A total of 60 participants will be enrolled: 30 participants will each be allocated to early access and standard access CR.

IMPACT: In the first prospective multicentre trial of its kind, EVADE will test an innovative post-MI rehabilitation strategy that has the potential to demonstrate the superior benefits of early access CR for attenuating ventricular remodeling, and increasing CR attendance, post-CR exercise adherence, exercise capacity, and HRQL. The results from EVADE would encourage the Canadian CR community to consider early access CR to further enhance readily available and existing CR programs. The knowledge gained from EVADE will inform clinical decision-making practices, influence future CR guidelines and policy, and will contribute to the ongoing goal of improving efficiency and effectiveness of the Canadian health care system.


Eligibility Criteria:
Inclusion Criteria:

* have a cardiologist-diagnosed non ST-segment elevation MI (NSTEMI) or ST-segment elevation MI (STEMI) identified as low risk based on the Global Registry for Acute Coronary Events (GRACE) risk score;
* have angiographic evidence of revascularization of the infarct-related artery that is defined as ≥80% patency;
* have an ejection fraction ≥35% (to exclude patients needing a cardioverter defibrillator) and \<50% (consistent with impaired heart pump function);
* reside within 100 km (1 hour travel time) of Saskatoon/Edmonton city limits;
* have been approved to attend CR by their attending physician.

Exclusion Criteria:

* have been hospitalized for a previous MI
* have a condition that precludes walk testing;
* have a contra-indication for cardiac MRI (i.e., pacemaker, pregnancy);
* index hospitalization \>10 days;
* undergo coronary artery bypass grafting;
* does not undergo coronary angiography.