Differential Changes of Left Ventricular Myocardial Deformation in Diabetic Patients with Controlled and Uncontrolled Blood Glucose: A Three-Dimensional Speckle-Tracking Echocardiography–Based Study

Subclinical impairment of left ventricular function in diabetic patients with or without obesity: A study based on three-dimensional speckle tracking echocardiography

AIMS

The aim of this study was to investigate subclinical left ventricular (LV) changes between type 2 diabetic patients with or without obesity using three-dimensional speckle-tracking echocardiography (3DSTE).

METHODS

A total of 77 type 2 diabetic patients, including 36 subjects with BMI < 25 kg/m(2) and 41 subjects with BMI ≥ 25 kg/m(2), as well as 40 age- and sex-matched controls (BMI: 18.5 ~ 24.5 kg/m(2)) were studied. Waist circumference was measured in diabetic patients with a BMI ≥ 25 kg/m(2) to determine whether abdominal obesity as a complication was present. Real-time three-dimensional (3D) full volume images of the left ventricle were recorded and analyzed. Left ventricular ejection fraction (LVEF), global longitudinal strain (GLS), global circumferential strain (GCS), global area strain (GAS), and global radial strain (GRS) were calculated and compared.

RESULTS

Compared with the controls, diabetic subjects without overall obesity had significantly lower GCS, GAS, and GRS (p < 0.05), as well as markedly lower GLS (p < 0.001). However, 3D-LVEF and all global strains in diabetic subjects with overall obesity were not only markedly lower compared with controls (p  <  0.002 and p < 0.001), but also significantly lower than those in diabetic subjects without overall obesity (p  <  0.002 and p  <  0.05). HbA1c and BMI showed negative impacts on all strains in diabetic patients. Meanwhile, the diabetic subjects with overall and abdominal obesity had significantly reduced GLS, GCS, GAS, and GRS compared with those with overall obesity only (all p  <  0.05).

CONCLUSIONS

Type 2 diabetic patients demonstrated early-stage subclinical LV deformation and dysfunction, whilst coexistent obesity resulted in further damage to myocardial contractility and reduced LVEF. 3DSTE was a sensitive method for detecting these abnormalities.

Right ventricle free wall mechanics in metabolic syndrome without type-2 diabetes: effects of a 3-month lifestyle intervention program

Background

Growing evidence demonstrates subtle left ventricular myocardial dysfunction in patients with metabolic syndrome (MetS), with central obesity, glucose intolerance and inflammation emerging as important contributors. Whether these results can be translated to the right ventricle (RV) is not yet fully elucidated. Furthermore, although lifestyle intervention favorably impacts MetS components and inflammatory biomarkers, its effect on RV myocardial function remains unknown today.

Methods

Thirty-nine MetS adults free of diabetes were enrolled in a three month lifestyle intervention program including diet and physical exercise, and compared with forty healthy controls. Blood biochemistry, echocardiography including tissue Doppler imaging (TDI), and vector velocity imaging of the RV free wall to assess global longitudinal strain (GLS) and strain rates (SR) were obtained at baseline and after the intervention.

Results

Compared with controls, MetS patients presented similar right atrial and RV morphology but reduced systolic (P = 0.04) and early diastolic (P = 0.02) velocities of the tricuspid annulus. They showed attenuated RV GLS (−21.4 ± 4.5vs-25.7 ± 4.9%, P < 0.001) as well as early diastolic (P = 0.003) and systolic (P < 0.001) SR. Multiple regression analyses revealed log PAI-1 active, (P < 0.001), log adiponectin, (P = 0.01), LV mass indexed (P = 0.004) and central fat (P = 0.03) as independent predictors of RV GLS (R² = 0.46, P < 0.001). Biological markers of MetS and inflammation as well as RV GLS (−21.8 ± 3.8vs-24.3 ± 3.0%, P = 0.009) and systolic (P = 0.003) and early diastolic (P = 0.01) SR, but not TDI indexes, significantly improved after diet and exercise training, and vector velocity imaging data in MetS following the lifestyle intervention no longer differed from controls.

Conclusions

MetS is associated with subtle impairments in both RV free wall diastolic and systolic myocardial function which could be partly related to central-obesity induced changes in pro- and anti-inflammatory cytokines and left ventricular remodeling. The favorable impact of healthy dieting and physical activity on RV free wall mechanics indicates that cellular and sub-cellular alterations responsible for the RV myocardial abnormalities are probably not permanent and modifiable throughout adequate interventional strategies.

Trial registration

American National Institutes of Health database NCT00917917.

The clinical benefits of adding a third dimension to assess the left ventricle with echocardiography

Three-dimensional echocardiography is a novel imaging technique based on acquisition and display of volumetric data sets in the beating heart. This permits a comprehensive evaluation of left ventricular (LV) anatomy and function from a single acquisition and expands the diagnostic possibilities of noninvasive cardiology. It provides the possibility of quantitating geometry and function of LV without preestablished assumptions regarding cardiac chamber shape and allows an echocardiographic assessment of the LV that is less operator-dependent and therefore more reproducible. Further developments and improvements for widespread routine applications include higher spatial and temporal resolution to improve image quality, faster acquisition, processing and reconstruction, and fully automated quantitative analysis. At present, three-dimensional echocardiography complements routine 2DE in clinical practice, overcoming some of its limitations and offering additional valuable information that has led to recommending its use for routine assessment of the LV of patients in whom information about LV size and function is critical for their clinical management.