Prevalence and Outcome of Brachial Artery Endothelial Function in Morbidly Obese Patients Undergoing Bariatric Surgery
The relation between obesity and ischemic heart disease (IHD) is under considerable debate. The reduction in all-cause mortality and, more specifically, the reduction in cardiac-related mortality seen after weight-loss surgery, may be due to regression or slowing developement of subclinical IHD. Function of cells lining the arteries (endothelium) is closely related to the state of IHD and its measurement can serve as a surrogate marker for the existence and severity of IHD. The investigators hypothesize that the prevalence of undiagnosed IHD in the morbidly obese population is high and that following surgery for weight reduction there is a halt in the progression, or even a regression in its severity.
The study includes measurement of endothelial function before and after weight-reducing surgery.
|Obesity, Morbid Ischemic Heart Disease||Other: Measurement of flow mediated dilation of brachial artery.|
|Study Design:||Observational Model: Cohort
Time Perspective: Prospective
|Official Title:||Prevalence and Outcome of Brachial Artery Endothelial Function in Morbidly Obese Patients Undergoing Bariatric Surgery|
- Flow-mediated (endothelial-dependent) vasodilatation (FMD) difference (before vs after surgery) [ Time Frame: 1 Year ]
|Study Start Date:||March 2009|
|Study Completion Date:||November 2014|
|Primary Completion Date:||November 2014 (Final data collection date for primary outcome measure)|
Other: Measurement of flow mediated dilation of brachial artery.
- Flow-mediated (endothelial-dependent) vasodilatation (FMD): Following a 2-minute baseline period, a longitudinal image of the artery will be obtained. A tourniquet placed around the forearm proximal to the target artery will be inflated to a pressure 50 mmHg higher than the subject's systolic blood pressure and held for 5 minutes. Cuff will be then deflated. A continuous scan will be performed at deflation, 60 and 90 seconds after cuff deflation, with frozen and Doppler measurements recorded at similar intervals to the baseline phase.
- NTG-induced (non-endothelial-dependent) vasodilatation (NTG): After vessel recovery, sublingual 375 mg of isosorbide dinitrate spray will be administered, and scanning will be performed continuously for 5 minutes thereafter.
Flow-mediated brachial artery reactivity will be measured and flow-mediated vasodilatation will be assessed with the subject's arm using a 15 MHz linear array ultrasound.
Please refer to this study by its ClinicalTrials.gov identifier: NCT00808652
|Sheba Medical Center|
|Tel Hashomer, Israel, 52621|