Echocardiographic evaluation of functional and morphological alterations in obesity: a comparison between obese individuals with and without Metabolic Syndrome

Background
Obesity has been identified as an independent risk factor for heart failure. The risk of heart failure is dependent on body mass index (BMI).
Aim
This study aimed to examine the effects of obesity on myocardial function and morphology, and to compare these alterations in obese individuals with and without metabolic syndrome (MetSC/- group).
Methods
A total 125 subjects with a BMI more than 25 kg/m2 underwent metabolic and clinical evaluation. An evaluation of conventional echocardiographic parameters and cardiac deformation by 2D speckle tracking echocardiography was
conducted. The mean age was 45.0 G 9.6 years (female: 58.7%), and the average BMI was 35.01 G 6.53. In 74% of the subjects, the duration of overweight/obesity was over 10 years. Metabolic syndrome was diagnosed in 54 patients (70%). Two dimensional echocardiographic evaluation showed that the MetSC group had a larger LA maximal volume and a LA volume indexed for body height than the MetS- group, but the differences were not statistically significant (P = 0.068, P = 0.098, respectively). The MetSC group had significantly lower LA ejection fraction compared to the MetS- group (LAEF%=46.89 vs 50.13, P=0.03). Regarding the strain analysis, it was also found that the MetSC group had significantly lower values for the peak longitudinal
deformation of LA in the reservoir phase (PALS) (P = 0.008). The LV mass indexed by height (LVMh) significantly differed between the two groups, despite
both being within the reference limits (P = 0.016). Conversely, both groups exhibited higher LV mass indexed by the square of height (LVMh2), with the MetSC group demonstrating a significantly higher values (P=0.002). Moreover, the mean values of global longitudinal strain (GLS) of the left ventricle were below the reference range in both groups, but significantly lower in the MetSC
group compared to theMetS- group (GLS=-20.7 vs -22.7, P=0.016) The peak mitral annular descent velocity (s’TDI) and the late diastolic velocity were significantly reduced in MetSC (P = 0.019 and P = 0.033, respectively).
Conclusion
Obesity itself causes substantial morphological and functional myocardial alterations, in particular if accompanied by metabolic abnormalities.