An observational study in Obesity and Gastric Bypass, sponsored by Washington University School of Medicine. Completed at 1 site in United States. Open to participants aged 18 Years to 55 Years. Per ClinicalTrials.gov, last updated 2016-05-04.
Sponsored by Washington University School of Medicine · Observational
Obesity affects more than 43 million Americans and is associated with an increased incidence of heart failure, sudden death, and cardiovascular death. We have shown that increasing obesity is independently associated with potentially detrimental LV structural and functional, and metabolic changes. Thus in order to increase our understanding of the effect of obesity on the heart, we wish to study the effect of significant weight loss on these parameters.
Thirty obese patients who weigh \<350#, the weight limit of the PET table, who are to undergo gastric bypass will be enrolled in this study. Written, informed consent approved by the Institutional Review Board of Washington University School of Medicine will be obtained from each subject before his/her participation in this study. Subjects will be compensated for their time. Subjects will undergo Medical Screening (Visit 1) consisting of a comprehensive medical evaluation: a history (questionnaire), physical examination, EKG, blood chemistries, kidney function, complete blood count, lipid profiles and pregnancy tests for women of childbearing age. Subjects who weigh \< 300# will have fat-free mass (body composition) determined by using a machine called DEXA. Measurement of Insulin Resistance (Visit 2): Subjects will undergo a hyperinsulinemic/euglycemic clamp and nonradiolabeled glucose infusion in order to define their level of insulin resistance and total body glucose turnover. This study will be performed in the GCRC.
Measurement of Myocardial Metabolism, Efficiency, Structure, and Function Measures and Total Body Fatty Acid Metabolism (Visit 3): Subjects will be admitted to the GCRC the evening before the PET imaging and at 6 pm will receive a standard meal. The next morning an 18-gauge intravenous catheter will be inserted into your arm vein. A catheter (small tube) will also be placed in the radial artery for the total body fat metabolism measurements \& for blood pressure monitoring. If the subject wishes it, they may have a Foley placed for urination during the PET scan studies. Myocardial PET imaging. Studies will be performed during fasting conditions at 8 am and ending at 1:00 pm. Each subject will be positioned within the scanner, and a 2-min data collection will be acquired to verify proper positioning before a 5-min. scan will be performed for generation of attenuation correction factors. Heart blood flow, oxygen consumption, and measures of fat metabolism will be obtained using PET imaging after the sequential injections of radiolabeled tracers as reported previously by our group. Blood pressure and heart rate will be monitored continuously and recorded throughout the image acquisition. During the scans, 5 blood samples (0, 2, 10, 20,\& 30 min) will be obtained for measurement of hormones, heart fuels (e.g. fats, lactate) and carbon dioxide levels.
Anonymous Genetic Tissue and Data Sampling: Draw and store 1 tablespoon of subject's blood, for a period of up to 10 years, to be used in future studies for screening for differences in genes related to heart membrane proteins or heart energy metabolism (including but not limited to genes known as KV1.5, KV2.1, PPAR, FATP, ACS, PGC-1). Echocardiography: Immediately following the PET imaging for oxygen consumption determination, subjects will undergo a complete 2D-, 3D-, and Doppler echocardiographic examination. Optison or Definity, depending on availability, clinically used intravenous contrast agents may be administered to aid with the acquisition of the ultrasound images. Total body fatty acid metabolism measurements: Simultaneous with the PET imaging, the subjects will undergo an infusion of a tracer amount of nonradioactive fat for measurement of total body fat metabolism. Blood samples will be drawn at predetermined times for this measurement.
3 Months s/p Gastric Bypass Surgery (Visit 4). Blood sampling
1 Year s/p Gastric bypass Measurement of Body Composition, Blood Chemistries, Lipid Levels, and Insulin Resistance (Visits 5 and 6). After the subjects have undergone gastric bypass for clinical reasons and are weight stable for 2 weeks (after approximately 1 year post-gastric bypass).
6,570 studies on the registry are indexed under Obesity; 1,718 are open to participants now.
This study's enrollment of 18 is below the median of 132 across 1,338 observational studies indexed under Obesity.
Browse Obesity studies →Washington University School of Medicine is the lead sponsor of 1,795 studies on the registry; 271 are open to participants now.
Of its 330 completed or terminated interventional studies of FDA-regulated products, 216 (65%) have results posted.
Counted across the registry records on this site, refreshed daily.
Patients who are to undergo gastric bypass surgery
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
measure the effect of marked weight loss induced by gastric bypass surgery on myocardial metabolism, efficiency, structure, and function in morbidly obese men and women
Time frame: measure at year 5
evaluate the relationship between changes in myocardial lipid metabolism with changes in whole-body lipid metabolism caused by weight loss
Time frame: measure at year 5
The record gives a start of Jul 2005, a primary completion of May 2012 and a completion of Jun 2014. It does not say whether these dates are actual or estimated.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in May 2016. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Washington University School of Medicine →