Favorable Changes in Cardiac Geometry and Function Following Gastric Bypass Surgery

Abstract

Objectives The objective of this study was to test the hypothesis that gastric bypass surgery (GBS) would favorably impact cardiac remodeling and function. Background GBS is increasingly used to treat severe obesity, but there are limited outcome data. Methods We prospectively studied 423 severely obese patients undergoing GBS and a reference group of severely obese subjects that did not have surgery (n = 733). Results At a 2-year follow up, GBS subjects had a large reduction in body mass index compared with the reference group (−15.4 ± 7.2 kg/m2 vs. −0.03 ± 4.0 kg/m2; p < 0.0001), as well as significant reductions in waist circumference, systolic blood pressure, heart rate, triglycerides, low-density lipoprotein cholesterol, and insulin resistance. High-density lipoprotein cholesterol increased. The GBS group had reductions in left ventricular (LV) mass index and right ventricular (RV) cavity area. Left atrial volume did not change in GBS but increased in reference subjects. In conjunction with reduced chamber sizes, GBS subjects also had increased LV midwall fractional shortening and RV fractional area change. In multivariable analysis, age, change in body mass index, severity of nocturnal hypoxemia, E/E', and sex were independently associated with LV mass index, whereas surgical status, change in waist circumference, and change in insulin resistance were not. Conclusions Marked weight loss in patients undergoing GBS was associated with reverse cardiac remodeling and improved LV and RV function. These data support the use of bariatric surgery to prevent cardiovascular complications in severe obesity.

Cardiac Remodeling in Obesity

“…62 Obesity is also a strong obstacle for achieving optimal blood pressure control by antihypertensive medications. 63 A clear effect of weight loss on reduction of LV mass has been more recently confirmed in a series of obese patients undergoing bariatric surgery, as described by Owan et al 64 In their study of 423 subjects who reduced their BMI by an average of 15 kg/m 2 , LV mass decreased by 30 g, on average. 64 The mechanisms of improvement of LV geometry with weight loss appear to be primarily hemodynamic.…”

“…63 A clear effect of weight loss on reduction of LV mass has been more recently confirmed in a series of obese patients undergoing bariatric surgery, as described by Owan et al 64 In their study of 423 subjects who reduced their BMI by an average of 15 kg/m 2 , LV mass decreased by 30 g, on average. 64 The mechanisms of improvement of LV geometry with weight loss appear to be primarily hemodynamic. In the study by Owan et al, 64 there was a correlation between change in BMI and changes in both diastolic blood pressure and LV mass index, 2 years after surgery.…”

“…Interestingly, the same group reported that midwall shortening improved after bariatric surgery, in parallel with improvement in LV geometry and a slight reduction in LV EF. 64 We interpret these data to mean that systolic function abnormalities detected by midwall shortening are closely related to the abnormalities in LV geometry. 92 Interestingly, strain values have also been demonstrated to decrease in parallel with increasing levels of relative wall thickness, as well as with increasing values for BMI and waist-to-hip ratio.…”

“…64 The mechanisms of improvement of LV geometry with weight loss appear to be primarily hemodynamic. In the study by Owan et al, 64 there was a correlation between change in BMI and changes in both diastolic blood pressure and LV mass index, 2 years after surgery. Interestingly, the changes associated with weight loss might also be macroscopically observed with the substantial reduction of epicardial fat, detected by 2D echocardiography.…”

Clinical Phenotypes in Heart Failure With Preserved Ejection Fraction

“…Sustained and substantial weight loss is more reliably attained by bariatric surgery than by lifestyle modifications and medications 145, 146, 147. Importantly, bariatric surgery improves LV relaxation and reverses concentric LV remodeling, with a substantial reduction in LV mass 148, 149, 150. In addition to decreasing arterial stiffness and blood pressure, bariatric surgery improves/cures OSA and diabetes 151.…”