Sex has a major impact on myocardial metabolism and blood flow. In subjects without heart failure men's hearts tend to use proportionally more glucose and women's hearts use more fat and have higher blood flow.
Obesity is a major risk factor for Heart Failure. In subjects without heart failure, increasing body mass index is predictive of increased blood flow and fatty acid metabolism in women, but not men.
To measure blood flow and metabolism we will be using radioactive materials and a PET (positron emission Tomography)scan to study the metabolism of the heart.
Hypotheses: 1) Women with nonischemic heart failure will have higher levels of heart blood flow and fatty acid metabolism and lower glucose metabolism rates than men with nonischemic heart failure 2) Patients with obesity-related HF have a myocardial metabolic profile that is similar to that of obese subjects without heart failure and different (higher FA metabolism) from that of nonobese Heart failure patients.
Heart failure (HF) and a systolic ejection fraction <45% per a recent echocardiogram report) Nonischemic HF New York Heart Association Class II-III Ambulatory Able to give informed consent On a stable medical regimen including the standard-of-care HF medications (i.e., a beta-blocker, ACE-inhibitor or angiotensin receptor blocker [ARB])
Exclusion criteria
Participants who were pregnant or lactating Actively losing weight Nonsedentary (performing aerobic exercise > 30 minutes x 3 times/week) Those who have more than Class I hypertension Those who require alterations in beta-blocker or ACE or ARB-inhibition medication Those with hypertrophic, constrictive, or restrictive cardiomyopathies Those unable to lie flat in the PET scanner Severe major organ system dysfunction (other than heart failure) Significant coronary artery disease by catheterization Those unable to give informed consent
