Evaluation of the Efficacy and Safety of Tirzepatide, a Dual GLP-1/GIP Agonist, on Functional Capacity in Reduced Ejection Fraction Heart Failure Patients With Obesity

Inclusion Criteria: * Age 18 years or older * Heart failure with reduced ejection fraction, defined as left ventricular ejection fraction ≤40% on echocardiography performed within the prior 3 months * Body mass index ≥27 kg/m², with at least one obesity-related comorbidity (hypertension, diabetes, or dyslipidemia) * Stable heart failure therapy for at least 4 weeks prior to enrollment, including beta-blockers, renin-angiotensin system inhibitors/angiotensin receptor-neprilysin inhibitors, and sodium-glucose cotransporter-2 inhibitors, if prescribed * Written informed consent Exclusion Criteria: * Acute heart failure decompensation or cardiac hospitalization within the prior 4 weeks * Uncontrolled blood pressure (systolic blood pressure \<90 mmHg or ≥180 mmHg) * Advanced renal impairment (estimated glomerular filtration rate \<30 mL/min/1.73m²) * Severe hepatic impairment (liver enzymes elevated to 3 times the upper limit of normal) * Active pancreatitis * Personal or first-degree family history of medullary thyroid carcinoma or multiple endocrine neoplasia type 2 * Pregnancy or breastfeeding * Known hypersensitivity to glucagon-like peptide-1 (GLP-1) or glucose-dependent insulinotropic polypeptide (GIP) receptor agonist drugs * Concurrent use of other weight-loss medications