What is the role of physical therapy (PT) in the different phases of cardiac rehabilitation?

Role of Physical Therapy in Cardiac Rehabilitation Phases

Physical therapists function as essential members of the multidisciplinary cardiac rehabilitation team, delivering supervised exercise training, conducting functional capacity assessments, and prescribing individualized exercise programs across all three phases, with their most critical and evidence-based role occurring in Phase 2 where they directly reduce cardiovascular mortality by 33% through structured, supervised exercise interventions. 1

Phase 1: Inpatient Cardiac Rehabilitation

Physical therapy during hospitalization focuses on early mobilization and patient education, though this phase notably lacks strong evidence-based exercise prescription principles compared to later phases 1. The specific PT interventions include:

• Basic mobility assessment and early ambulation to prevent deconditioning during the acute recovery period 1
• Patient education on cardiac event recovery expectations, disease management fundamentals, and safe activity progression 1
• Initial cardiovascular risk factor identification through problem-focused history and physical examination, assessing cardiovascular stability and musculoskeletal limitations 1
• Psychological support initiation to address anxiety and depression commonly present after acute cardiac events 1

The evidence base for Phase 1 protocols remains weak, with subjective approaches that fail to incorporate the three fundamental principles of exercise prescription: specificity, overload, and reversibility 2. This represents a significant gap in evidence-based physiotherapy practice during the inpatient phase.

Phase 2: Early Outpatient Cardiac Rehabilitation (Most Critical Phase)

Phase 2 represents the most substantive evidence base for physical therapy's role, with Class I, Level A recommendations supporting its ability to reduce cardiovascular mortality by 33% and recurrent myocardial infarction by 36%. 1, 3

Core PT Functions in Phase 2

Physical therapists deliver the following evidence-based interventions during this 3-6 month intensive period:

• Functional capacity evaluation using graded exercise testing (treadmill or cycle ergometry) to establish baseline exercise capacity and guide prescription 1
• Structured, supervised exercise sessions with prescribed intensity based on individual hemodynamic responses and musculoskeletal limitations 1
• Individualized exercise prescription using stationary bicycle, treadmill, calisthenics, walking, or jogging modalities 3
• Continuous monitoring and modification based on ECG telemetry (for high-risk patients), blood pressure responses, and symptom presentation 3
• Progressive exercise intensity advancement following evidence-based protocols to achieve moderate-intensity aerobic training as the standard 3

Supervision Requirements

The regulatory framework for Phase 2 demands specific PT practice parameters:

• Direct physician supervision with immediate availability is required, though the physician need not be physically present in the exercise room itself 1
• All PT staff must complete basic life support (BLS) training, with at least one staff member holding advanced cardiac life support (ACLS) certification 1
• Experience in exercise training for patients with coronary heart disease is mandatory, along with immediate access to functional emergency resuscitation equipment 1

Clinical Outcomes Achieved Through PT Interventions

The evidence demonstrates that PT-delivered exercise training in Phase 2 produces:

• 33% reduction in cardiovascular mortality (p=0.02) when delivered as comprehensive cardiac rehabilitation 1
• 36% reduction in recurrent myocardial infarction at 3-year follow-up (p=0.049) 1, 3
• Significant improvement in health-related quality of life, with a -5.7 point improvement on the Minnesota Living with Heart Failure questionnaire (95% CI -10.6 to -0.7 points, p=0.025) 1
• Reduced all-cause hospitalization risk compared to usual care 4

Phase 3/4: Long-Term Maintenance Cardiac Rehabilitation

Physical therapy transitions to a less intensive supervisory role focused on sustaining behavioral changes and independent exercise capacity 1. The specific PT functions include:

• Continued exercise training with reduced supervision intensity, promoting independent exercise and physical activity maintenance 1
• Periodic functional capacity reassessment to monitor progress and adjust exercise prescriptions 1
• Long-term physical activity promotion to prevent deconditioning and maintain cardiovascular fitness 4
• Quality of life maintenance rather than mortality reduction, as the evidence base for Phase 3/4 focuses more on sustained behavioral change 1

The supervision requirements are less stringent than Phase 2, with emphasis on patient autonomy and self-management 1.

Alternative PT Delivery Models

Home-based and technology-based cardiac rehabilitation programs represent critical alternatives to traditional center-based models, achieving equivalent efficacy and safety with potentially higher adherence rates. 3

Home-Based PT Programs

• Appropriate for low-risk, clinically stable patients who have successfully completed initial supervised sessions 3
• Require active ongoing contact through home visits, telephone consultations, or technology platforms to maintain quality assurance 3
• Achieve equivalent clinical outcomes to center-based programs when properly implemented 3

Technology-Based PT Delivery

• Telerehabilitation represents an emerging alternative, especially critical for low-income and middle-income countries where cardiac rehabilitation services are scarce 1
• Supported by accessible digital technology including Internet and mobile phone platforms for remote monitoring and coaching 4
• Expedited by COVID-19 pandemic, which forced rapid adoption of home-based and technology-based models when center-based programs paused services 4

Multidisciplinary Integration Requirements

Physical therapists cannot function in isolation but must integrate within a comprehensive team structure:

• Work collaboratively with cardiologists, general practitioners, nurse specialists, dietitians, and psychologists, all trained in core competencies for cardiac rehabilitation delivery 1
• Maintain close communication with the treating physician to maximize effectiveness and promote long-term behavioral change 3
• Participate in program oversight under a physician-director responsible for ensuring policies align with evidence-based guidelines and safety standards 1

Critical Implementation Challenges and Pitfalls

Despite robust evidence supporting PT's role in cardiac rehabilitation, significant barriers persist:

• Severe global underutilization, with only 5-50% of eligible patients receiving rehabilitation services 1
• Referral rate disparities by diagnosis: post-MI referral at 29%, post-PCI at 51%, post-CABG at 75%, and heart failure less than 10% 3
• Poor access among vulnerable populations, including older adults, women, non-white and ethnic minority groups, and patients with multimorbidity 3
• Declining adherence after 6 months, requiring long-term reinforced interventions coordinated by the rehabilitation team to maintain behavioral changes 1

The most critical pitfall is failing to refer eligible patients to Phase 2 cardiac rehabilitation, where the strongest evidence exists for mortality reduction through PT-delivered exercise training. 1 All patients with acute coronary syndrome, heart failure with reduced ejection fraction, or post-revascularization should receive automatic referral before hospital discharge or at the first follow-up visit (Class I, Level A recommendation) 3.

Specific Patient Populations Requiring PT Services

Physical therapists must be prepared to deliver cardiac rehabilitation across diverse cardiac diagnoses:

• Acute coronary syndrome patients (Class I, Level A recommendation for referral) 3
• Post-coronary revascularization patients (PCI or CABG) (Class I, Level A recommendation) 3
• Heart failure with reduced ejection fraction (Class I, Level A recommendation for exercise training safety and effectiveness) 3
• Emerging populations requiring further research: heart failure with preserved ejection fraction, atrial fibrillation, congenital heart disease, post-valve surgery, and post-heart transplantation 1