Upper Extremity Function in Patients With Reduced Ejection Fraction Heart Failure and Cardiac Implantable Electronic Devices

Inclusion Criteria: * Adults aged ≥18 years, * Left ventricular ejection fraction ≤40%, * Implanted cardiac defibrillator (ICD) or cardiac resynchronization therapy (CRT), * Diagnosed with heart failure, * No complications found during the last device check, * Clinically stable for the past month, with any accompanying chronic diseases (such as hypertension, diabetes) under control, and willing to participate in the study. Exclusion Criteria: * Patients with neurological, orthopedic, or psychiatric disorders, * History of shoulder surgery or shoulder injury, * Individuals with cognitive or mental disorders that would prevent them from understanding the tests administered in the study, or patients who are unwilling to participate