The purpose of this study is to develop and evaluate a frailty-specific prehabilitation program for patients awaiting cardiac surgeries/procedures. The program aims to improve functional capacity, frailty level, cardiac-related physical functioning, health-related quality of life (HRQoL), psychological distress, major adverse cardiovascular and cerebral events (MACCE), hospital length of stay, and readmission rates.

Cardiovascular disease is a leading cause of disability and morbidity globally, particularly in older adults. Frailty, a geriatric syndrome commonly seen in cardiac patients, complicates their perioperative care and leads to worse outcomes.

Prehabilitation, which optimizes patients' physiological and functional capacities before surgery, has shown promise in general cardiac patients but requires a more comprehensive approach for frail individuals. This randomized controlled trial will recruit 50 Chinese adults awaiting elective cardiac surgeries/procedures in Hong Kong. Participants will be randomly assigned to either the intervention group, receiving a comprehensive prehabilitation program, or the control group, receiving routine preoperative care. Assessments will be conducted at baseline and at three postoperative time points.

The findings will contribute to our understanding of the impact of frailty on postoperative outcomes and help develop strategies to improve patient care. Ultimately, this study aims to reduce healthcare burdens associated with cardiac disease-related morbidity and disability.

Cardiovascular disease is a major cause of disability and morbidity worldwide. With advances in medical technology and care, patients with cardiovascular disease often live to an advanced age. In the older cohort, conditions particularly associated with age-related atherosclerosis and calcification dominate, such as coronary artery disease and valvular heart disease. Surgical interventions remain the treatment-of-choice for patients with advanced cardiac conditions. However, this vulnerable cohort is still afflicted by a higher risk of mortality, postoperative complications, and longer hospital stays, particularly those with frailty.

Frailty is a clinical condition characterized by reduced reserve capacity and excessive vulnerability to increased risk of adverse health outcomes when exposed to stressors. Its prevalence increases in the population with cardiovascular disease and is a significant prognostic indicator for predicting postoperative outcomes in cardiac patients. The best strategy to minimize the prognostic impacts of frailty on cardiac patients should be intervened at the preoperative stage, which may be achieved through prehabilitation.

Prehabilitation refers to preoperative interventions designed to optimize patients' physical and psychological readiness for surgery. The international guidelines of the Enhanced Recovery After Surgery Society (ERAS) suggest the prehabilitation for cardiac surgical patients should be exercise-based, supplemented with education, dietary modification, and psychological support. These components can prepare patients to withstand stressful events during surgery through reducing sympathetic over-activity and improving their physiological and functional capacities.

Accumulating evidence indicates the effectiveness of prehabilitation for general cardiac patients through respiratory muscle and aerobic training; however, few studies have investigated those with frailty, who are in greater need. Among the limited trial that particularly focus on frail patients, encouraging findings have been reported that preliminarily indicate their efficacy and safety profile. There are also some ongoing trials testing prehabilitation for frail cardiac patients registered in trial registries.

Despite the promising results, there are several major knowledge gaps in the studies of prehabilitation for frail cardiac patients. First, most of these trials are testing a single frailty-reversing strategy, either nutritional or exercise interventions, which are less comprehensive to address the urgent needs of surgical patients. Second, the protocols of those exercise programs are mainly aerobic-focused, deviating from the principles of exercise prescription suggested for frailty management. Third, all completed and ongoing trials are center-based using gymnasium equipment, which has several limitations that jeopardize the feasibility, availability, and effectiveness of the programs.

To conclude, more comprehensive and accessible prehabilitation programs are needed for frail cardiac patients to address their complex needs and improve their surgical outcomes. A hybrid approach, using eHealth to supplement in-person patient support, could offer a more practical and feasible solution. Further research is required to develop and evaluate such programs and to fill the knowledge gaps in prehabilitation for frail cardiac patients.

Inclusion Criteria:

1. A confirmed schedule for elective CABG, valve repair/replacement, or combined CABG and valve repair/replacement, or TAVI
2. Mild to moderate frailty at the time of recruitment, indicated by a Clinical Frailty Scale score between 4 and 6
3. At least 5 weeks of procedural waiting time
4. Physically fit for prehabilitation according to the surgeon/cardiologist's endorsement on a risk-assessment checklist
5. Living with family
6. Using an electronic device with internet access (patient/family).

Exclusion Criteria:

1. Impaired cognition (Abbreviated Mental Test score ≤6) or communication
2. With physical limitations to exercise

The post-intervention data collector (research assistant) will be blinded to the group allocation to avoid performance and detection biases.