Unsaturated Fatty Acids Enriched-diet to Improve Cardiorespiratory Fitness, Metabolic Flexibility and Glucose Tolerance in Obese Patients

Twelve obese HFpEF subjects with exercise intolerance (reduce cardiorespiratory fitness
measured at maximal cardiopulmonary exercise test [CPX]) will be assigned to a single-arm
open-label dietary intervention in which subjects are encouraged and financially supported to
increase daily UFA consumption. The investigators will measure dietary compliance with a
validated 24-hour dietary recall and with objective operator-independent biomarkers of UFA
consumption.

The investigators will also measure the effects of UFA supplementation on: metabolic
flexibility, glucose tolerance and body composition. Participants will have the option to
participate in overnight session in the whole indirect calorimeter room (WIC) at baseline and
at the end of the study.

Major Inclusion Criteria:

- Body Mass Index (BMI) ≥30 kg/m2 (obesity) or total body fat percentage >25% in men and
>35% in women

- A confirmed clinical diagnosis of stable HF (New York Heart Association [NYHA] class
II-III) on maximally tolerated heart failure (HF) optimal medical regimen (without
major changes in the prior month)

- Left Ventricular Ejection Fraction (LVEF)>50% documented in the prior 12 months

Major Exclusion Criteria:

- Concomitant conditions or treatment which would affect completion or interpretation of
the study (i.e.,physical inability to walk or run on treadmill);

- Significant ischemic heart disease, angina, uncontrolled arterial hypertension, atrial
fibrillation, moderate to severe valvular disease, chronic pulmonary disease, anemia
(Hemoglobin<10 g/dL)

- Electrocardiography (ECG) changes (ischemia or arrhythmias) that limit maximum
exertion during cardiopulmonary exercise test

- Comorbidity limiting survival

- Stage IV-V kidney disease (estimated Glomerular Filtration Rate<30)

- Fluid overload

- Pregnancy

- Current use of unsaturated fatty acids (UFA) supplement (i.e., omega-3).

- Inability to give informed consent