Impact of Cardiac Rehabilitation on Patient Outcomes

Background and Rationale:Cardiovascular diseases remain a leading cause of morbidity and mortality worldwide. Comprehensive cardiac rehabilitation (CR) programs are widely recognized as a cornerstone of secondary prevention, aiming to improve physical fitness, psychological well-being, and overall health status in cardiac patients. However, real-world retrospective data assessing the multi-dimensional impact of structured CR-encompassing functional capacity, psychological distress (depressive symptoms), health-related quality of life, and sleep quality-simultaneously remain crucial for optimizing patient care protocols.

Study Objectives:The primary objective of this retrospective study is to evaluate the changes in clinical, functional, and psychosocial outcomes following participation in a structured cardiac rehabilitation program. Specifically, the study aims to compare pre- and post-rehabilitation measures regarding: Functional exercise capacity, depressive symptom severity, health-related quality of life (HRQoL), sleep quality.

Study Design and Patient Population:This study utilizes a retrospective observational design. Clinical records and institutional databases will be systematically reviewed to identify patients with heart disease who were admitted to and completed a structured cardiac rehabilitation program.

Data Collection and Outcome Measures: All patient data regarding baseline characteristics, clinical history, and pre- and post-rehabilitation assessments are routinely collected as part of standard clinical care. The primary and secondary outcome measures to be extracted and analyzed include:

• Functional Capacity: Assessed using the 6-Minute Walk Test (6MWT), measuring the distance walked in 6 minutes as an indicator of submaximal aerobic capacity.
• Depressive Symptoms: Evaluated via the Beck Depression Inventory (BDI), a self-report questionnaire measuring the severity of depression.
• Health-Related Quality of Life (HRQoL): Evaluated using the Short Form-36 (SF-36) health survey, covering both physical and mental component summaries.
• Sleep Quality: Assessed using the Pittsburgh Sleep Quality Index (PSQI), measuring sleep habits and disturbances over a 1-month time interval.

Statistical Analysis: De-identified data will be analyzed using JASP statistical software. Normality of distribution for continuous variables will be tested using the Shapiro-Wilk test or Kolmogorov-Smirnov test. Paired-samples t-tests or Wilcoxon signed-rank tests will be utilized to compare pre-rehabilitation (baseline) and post-rehabilitation outcomes, depending on data normality. A p-value of < 0.05 will be considered statistically significant.

Inclusion criteria

• Patients diagnosed with coronary artery disease (CAD), status post-myocardial infarction (MI), stable angina, or those who have undergone cardiac surgery
• Availability of complete pre- and post-rehabilitation clinical records, including 6-Minute Walk Test (6MWT), BDI, SF-36, and PSQI scores.
• Patients classified as stable by a cardiologist prior to the initiation of the exercise program.

Exclusion criteria

• Presence of severe orthopedic, neurological, or musculoskeletal disorders that prevent the performance of the 6-Minute Walk Test or exercise training.
• Patients with severe cognitive impairment
• Unstable angina pectoris, uncontrolled arrhythmias, or advanced heart failure (NYHA Class IV) that contraindicates aerobic exercise.
• Patients who dropped out of the rehabilitation program before completion or had more than a 20% absence rate in sessions.
• Patients who underwent major non-cardiac surgery within the last 3 months.