Weight reduction surgery is associated with substantial long term reduction in left ventricular mass

Background

Uncomplicated obesity is associated with left ventricular hypertrophy, which is an independent risk factor for cardiovascular events. Excess body weight has a linear relationship with vascular mortality. We have previously shown that weight reduction surgery is associated with LV mass reduction 1 year later. Here we have used CMR to investigate the effects of weight reduction surgery at 3 years.

Methods

We followed up 6 patients who had undergone Roux-en-Y gastric bypass surgery for obesity (Body Mass Index 46.7 ± 3.8 kg/m²). All subjects had no other identifiable cardiovascular risk factors: diabetes, hypertension, hypercholesterolaemia, smoking, obstructive sleep apnoea or known cardiac disease. The subjects had CMR scans (1.5 Tesla, Siemens, Erlangen, Germany) and body composition analysis performed at baseline, 1 and 3 years.

Results

At one year, there was a significant reduction in BMI by 13.2 ± 3.8 kg/m², representing 28% of pre-operative BMI (Figure 1). LV mass had decreased by 15% from 149 g to 126 g (p < 0.01, Figure 2) during this period. At 3 years, although body mass index did not decrease further significantly, there was a significant additional reduction in LV mass from 126 g to 110 g (p = 0.04), representing a further 11% reduction in LV mass from baseline.

Figure 1

Figure 1

Figure 2

Figure 2

Conclusion

Over 3 years, weight reduction surgery is associated with a significant progressive reduction in LV mass, which continues even after BMI has stabilised after 1 year. This represents long-term LV remodelling in response to marked weight loss.