Abstract 4190: Weight Loss After Bariatric Surgery Normalizes Aortic Distensibility and Left Ventricular Function in Subjects with Morbid Obesity: A 3-year Follow-Up Study
Mordid obesity is associated with high incidence of heart failure. Aortic distensibility (AoD) is an important determinant of left ventricular (LV) function. We investigated whether a) increased body mass index (BMI, kg/m2) is associated with impaired AoD and LV function b) weight loss after bariartic surgery (gastric by-pass) is associated with changes of AoD and LV function in subjects with morbid obesity after 3 and 36 months of follow-up.
Methods: We studied 60 subjects (mean age 35±11 years) with morbid obesity (BMI>40 kg/m2) by 2D, and Doppler Echocardiography. AoD was calculated using the formula 2 x (pulsatile change in aortic diameter)/[diastolic aortic diameter x (aortic pulse pressure)](normal range:2.4 – 4.4 cm2xdyn(−1)x10(−6)).Aortic diameters were measured 3cm above the aortic valve by 2D guided M-mode echocardiography and aortic pulse pressure was obtained simultaneously by cuff sphygmo-manometry 3 and 36 months after surgery.
Results: All patients had normal systolic function before and after surgery. Aortic distensibility was severely impaired before surgery (table⇓). Increasing BMI was related to decreasing AoD (r=0.43,p<0.01) and increased interventicular septum (IVS) and posterior (PW) wall thickness (IVS: r=0.57, PW: r=0.58, p<0.01) before surgery. Decreasing AoD was related to prolonged IVRT (r=0.43, p<0.01) and DT (r=0.40, p<0.05). Three months after surgery, BMI, LV diastolic diameter (LVDmm), IVS(mm), PW(mm), isovolumic relaxation time (IVRT sec) and decelaration time ( DTsec) were reduced whereas AoD was increased. (table⇓, p<0.01). After 36 months, there was a further improvement in AoD and BMI The decrease of BMI was related to improvement of AoD at 36 months of f/u (r=0.40 p=0.008).
Conclusion.. Weight reduction after bariatric surgery normalises aortic distensibility, reduces LV hypertrophy and thus, improves LV diastolic function early and 36 months after surgery.