The purpose of this study is to assess the performance of 68Ga- FAPI PET in heart failure with preserved ejection fraction (HFpEF)

HFpEF Group Inclusion:

• Patients aged ≥ 30 years old with exertional dyspnea (NYHA II and III) and LVEF ≥50%
• BMI ≥ 30
• New diagnosis of HFpEF based on RHC at baseline (elevated PCWP at rest and/or during exercise)

HFpEF Group Exclusion:

• Primary cardiomyopathy or pericardial disease or ≥ moderate valvular disease
• Dyspnea due to lung disease or CAD
• Severe anemia, liver, or renal disease
• Active cancer
• Systemic active inflammatory or autoimmune disease (e.g. rheumatoid arthritis, SLE, etc.)
• Recent hospitalization (< 30 days) or coronary revascularization (< 90 days)
• Patients already taking SGLT2i and/or GLP-1A
• Pregnant or breastfeeding
• Inability to tolerate supine position for the PET/CT or CMR scans.
• Contraindications for safe CMR scanning (e.g., uncontrolled claustrophobia, cochlear implant, implanted neural stimulator)
• Known gadolinium allergy
• Presence of implantable cardiac pacemaker or defibrillator or mechanical valve.

Cardiac Sarcoid Group Inclusion:

• Ambulatory patients aged ≥ 18 years old
• New referrals to the Sarcoid Clinic with a confirmed but untreated diagnosis of definite or probable CS based on 2014 HRS consensus (see Table 2)
• With a positive cardiac 18F-FDG PET scan within 30 days.

Cardiac Sarcoid Group Exclusion:

• Already on immunosuppressive therapy
• Pregnant or breastfeeding
• Severe liver or renal disease (estimated GFR < 30 or dialysis-dependent)
• Recent coronary revascularization (< 90 days)
• Active cancer
• Known gadolinium allergy
• Inability to tolerate supine position for the PET/CT or CMR scans.
• Contraindications for safe CMR scanning (e.g., uncontrolled claustrophobia, cochlear implant, implanted neural stimulator)
• Presence of implantable cardiac pacemaker or defibrillator or mechanical valve.

Healthy Controls Group Inclusion:

• Adults ≥ 30 years old
• No major chronic disease (cardiopulmonary, inflammatory, autoimmune, cancer, renal or liver impairment, etc.)
• No intake of relevant medication, defined as regular intake of at least one of the following: anticoagulants, antiplatelets, antihypertensive / diuretics, antidiabetics, antiarrhythmic, immunosuppressants, chemotherapy, antibiotics/antivirals/antifungals

Healthy Controls Group Exclusion:

• BMI ≥ 30
• Pregnant or breastfeeding
• Known gadolinium allergy
• Inability to tolerate supine position for the PET/CT or CMR scans.
• Contraindications for safe CMR scanning (e.g., uncontrolled claustrophobia, cochlear implant, implanted neural stimulator)