Previous research has confirmed that patients undergoing percutaneous coronary intervention (PCI) can benefit from cardiac rehabilitation programs. However, there is a paucity of studies on Phase I cardiac rehabilitation commenced within three days following PCI in patients with acute myocardial infarction (AMI). Consequently, the objective of the study is to demonstrate whether Phase I cardiac rehabilitation can improve the prognosis at 12 months when compared with the control group. The primary endpoint is the Seattle Angina Questionnaire (SAQ) score at 12 months for the patients. The principal hypothesis of the study is that Phase I cardiac rehabilitation will improve the long-term prognosis for AMI patients at 12 months after PCI.

Inclusion Criteria:

1. Patients with AMI (including STEMI and NSTEMI) who were treated in the CCU (Coronary Care Unit) for more than 12 hours after emergency PCI;
2. Patients who are expected to meet the discharge criteria without the need for repeat PCI during the current hospital stay after PCI;
3. No chest pain episodes within 8 hours, with no recurrence of myocardial infarction; remained hemodynamically stable;
4. No further increase in serum levels of cardiac biomarkers such as Creatine Kinase -MB (CK-MB) and cardiac troponins (cTn).

Exclusion Criteria:

1. Patients with Killip class III or higher, or symptoms and signs of acute pulmonary edema and respiratory distress;
2. Malignant arrhythmias that cause hemodynamic instability and potentially life-threatening conditions;
3. Mechanical lesions such as ventricular wall rupture, valve or tendon rupture;
4. Patients who have not yet been weaned off ECMO, IABP, temporary pacemakers, CRRT;
5. Patients with liver or kidney dysfunction (transaminase exceeded three times the upper limit of normal; EGFR<30 ml/(min·1.73m^2)) or advanced malignant tumors;
6. Patients who cannot undergo exercise rehabilitation due to orthopedic or psychiatric diseases;
7. Patients with language impairment;
8. Patients currently undergoing systematic training or participating in other clinical trials without reaching the primary endpoint collection time;
9. Researchers believe that patients are not suitable for participation in this study or have not obtained an informed consent form.