Observational study of muscle and blood vessel function in HFpEF, before and after weight-loss medication

This project is an observational study in patients with heart failure with preserved ejection fraction (HFpEF) who are candidates for treatment with weight loss medication to manage obesity or diabetes as part of their standard clinical care. This study will include multiple experimental visits before and after treatment (minimum 7 percent weight loss, between 9-12 months) to understand how increased adiposity and inflammation effects skeletal muscle and cardiovascular health and function and to examine the effect of medically directed weight loss on skeletal muscle health and exercise tolerance.

The objective of this study is to

1. Define the mechanisms by which adiposity impairs exercise hemodynamics, microvascular function, and oxygen transport/utilization in patients with HFpEF. 2. Determine if intensive medically directed weight loss can reduce microvascular inflammation and normalize exercise hemodynamics. 3. Quantify the effect of medically directed weight loss on skeletal muscle function and catabolism.

Hypotheses

1. Perfusion of subcutaneous adipose tissue disrupts blood flow distribution and impairs muscle microvascular perfusion and exercise hemodynamics. 2. Extramyocellular muscular lipid deposition and microvascular endothelial inflammation is associated with reduced capillarity and impaired microvascular perfusions, while intramyocellular triglyceride content is associated with poor skeletal muscle oxidative capacity, 3. Intensive weight loss will improve exercise hemodynamics, microvascular perfusion, and reduce muscular inflammation, and resistance training will augment these effects.