Inclusion Criteria
- Age ≥ 30 years
- Symptoms of severe dyspnea (NYHA Class III-IV) without evidence of a non-cardiac or ischemic explanation for dyspnea
- Ejection fraction of ≥50%, determined on most recent imaging study within the preceding 2 years (730 days), with no change in clinical status, suggesting potential for deterioration in systolic function.
- Documentation history of at least one of the following:
Any previous hospitalization for HF (>30 days prior to enrollment) with radiographic evidence of pulmonary congestion (pulmonary venous hypertension, vascular congestion, interstitial edema, pleural effusion) or Elevated NT-proBNP (>300 pg/ml or >600 pg/ml if in atrial fibrillation) or Echocardiographic evidence of diastolic dysfunction/elevated filling pressures manifested by medial E/e' ratio ≥15 and/or left atrial enlargement and chronic treatment with a diuretic for signs or symptoms of heart failure or Historical catheterization documented elevated filling pressures at rest (PCWP ≥15 or LVEDP ≥18) or with exercise (PCWP ≥25), prior to consent.
- Catheterization documented elevated filling pressures at rest (PCWP ≥15 or LVEDP ≥18) or with exercise (PCWP ≥25) during the screening/baseline visit (after consent)
- Ambulatory with ability to complete 6-minute walk and cardiopulmonary exercise test (not wheelchair / scooter dependent)
Exclusion Criteria
- Recent (< 30 days) hospitalization for heart failure
- Left (> 6 cm) ventricular dilation noted on cardiac imaging study (echocardiography or MRI) within 6 months prior to enrollment.
- Any hemoglobin (Hgb) < 8.0 g/dl within 30 days prior to enrollment
- Any GFR < 20 ml/min/1.73 m2 within 30 days prior to enrollment
- Significant alternative cause of dyspnea such as severe chronic obstructive pulmonary disease or ischemia that is a primary contributor to symptoms, in the opinion of the Investigator.
- Myocardial infarction (MI), unstable angina, catheter ablation for atrial fibrillation, biventricular pacing device implant, or percutaneous coronary intervention (PCI) within 90 days prior to enrollment
- Any prior cardiac surgery
- Documented stroke, CVA, TIA, deep vein thrombosis, pulmonary emboli, or suspected neurological event within 180 days prior to enrollment
- Diagnosis of obstructive hypertrophic cardiomyopathy
- Known infiltrative cardiomyopathy (e.g., amyloid)
- Known pericardial disease (constriction, pericarditis, tamponade)
- Known allergy or sensitivity to contrast media that cannot be adequately pre-treated prior to the procedure.
- Active myocarditis
- Significant congenital anomaly, anatomic, or comorbid medical problem that, in the opinion of the Investigator, would preclude enrollment in the study.
Active collagen vascular disease
- Significant valvular heart disease (greater than mild stenosis or greater than moderate regurgitant lesions)
- Acute or chronic severe liver disease, as evidenced by any of the following: encephalopathy, variceal bleeding, INR > 1.7 in the absence of anticoagulation treatment.
- Untreated severe obstructive sleep apnea (if known)
- Implantation or planned implantation of any left atrial shunts or implantable devices used to treat heart failure.
- Terminal illness (other than HF) with expected survival of less than 1 year
- Enrollment or planned enrollment in another therapeutic clinical trial in the next 6 months.
- Inability to comply with planned study procedures or follow-up requirements, including cardiac MRI (e.g., claustrophobia or absolute contraindication to MRI)
- Women who are currently pregnant, plan to become pregnant, or are currently breastfeeding.
- Intolerance or contraindication to colchicine