Usefulness of combined quantitative assessment of myocardial perfusion and velocities by myocardial contrast and doppler tissue echocardiography during coronary blood flow reduction

The diagnostic value of echocardiography combined with serum Hcy and PCSK9 in coronary heart disease

Coronary heart disease (CHD) is one of the most common cardiovascular diseases. This study analyzed the diagnostic value of echocardiography combined with serum homocysteine (Hcy) and proprotein convertase subtilisin 9 (PCSK9) in CHD. Here, 108 CHD patients were selected as the study group. Additionally, 108 patients with suspected CHD excluded by coronary angiography were selected as the control group. Serum Hcy and PCSK9 levels were detected by circulating enzymatic and biochemical analysis assay. The contrast echocardiography showed that the contrast agent filling velocity (β) and the maximum number of microbubbles (A) in the study group were declined compared to the control group. Serum Hcy and PCSK9 levels in the study group were higher than those in the control group. In addition, β, A, Hcy and PCSK9 are important influencing factors of CHD. The coronary artery disease branch numbers and the degree of stenosis in CHD patients were negatively correlated with β and A values, and positively correlated with serum Hcy and PCSK9 levels. β, A combined with serum Hcy and PCSK9 levels have diagnostic value for CHD, and are significantly correlated with the severity of CHD.

Impact of diet and exercise training-induced weight loss on myocardial mechanics in severely obese adolescents

OBJECTIVE

Recent findings indicated silent incipient myocardial dysfunction in juvenile obesity despite normal global cardiac function. The present study investigated whether lifestyle intervention is able to favorably impact these obesity-related myocardial abnormalities and whether improvements are related to changes in insulin resistance and cardiac remodeling.

DESIGN AND METHODS

Twenty-eight severe obese adolescents (OB) participated in a 9 month lifestyle intervention program (LIP) based on aerobic exercise and diet. Twenty healthy adolescents (CG) served as controls. Conventional echocardiography and myocardial mechanics were obtained at baseline and follow-up along with insulin resistance.

RESULTS

Insulin sensitivity improved (P < 0.001) and body weight decreased (P < 0.001) consecutive to LIP. At baseline, OB had depressed longitudinal (L) strain (CG: -18.3 ± 2.6, OB: -14.2 ± 3.6%, P < 0.001) and enhanced twist compared to controls. The LIP in OB restored L strain to normal values (-16.9 ± 3.5%, NS), whereas it did not affect twist mechanics. From stepwise multiple regression analysis, only baseline L strain and changes in BMI Z-score (r(2) -adjusted = 0.49, P < 0.001) emerged as independent predictors of L strain changes.

CONCLUSIONS

Juvenile obesity is associated with myocardial mechanic abnormalities that can be partly corrected by lifestyle intervention. Restoration of longitudinal myocardial function occurs in the absence of left ventricular remodeling changes and is not associated with insulin resistance improvements.

Two-dimensional strain and twist by vector velocity imaging in adolescents with severe obesity

The prevalence of severe obesity is increasing worldwide in adolescents. Whether it is associated with functional myocardial abnormalities remains largely unknown, potentially because of its frequent association with other cardiovascular risk factors and also use of insensitive techniques to detect subclinical changes in myocardial function. We used 2D vector velocity imaging (VVI) to investigate early changes in left ventricular (LV) myocardial function in youths with isolated severe obesity. Thirty-seven asymptomatic severely obese adolescents free of diabetes and hypertension, and 24 lean controls were enrolled. LV longitudinal, basal, and apical circumferential strain, strain rate (SR), rotations, and LV twist were measured. Obese adolescents had greater LV mass and reduced systolic and early diastolic tissue Doppler imaging (TDI) velocities than lean counterparts. L strain (-24%) and systolic and early diastolic SR were also diminished in the obese, whereas no intergroup differences existed for the circumferential deformation indexes. LV twist was more pronounced in the obese (+1.7°, P < 0.01) on account of greater apical rotation only (4.1 ± 0.9 vs. 5.2 ± 1.2°, P < 0.01), potentially compensating for the loss in longitudinal function. Systolic-diastolic coupling, an important component of early filling and diastolic function, was maintained with severe obesity. No intergroup differences were reported regarding time to peak values for all VVI indexes highlighting that dynamics of strain and twist/untwist along the cardiac cycle was preserved with severe obesity. Isolated severe obesity in adolescents, at a preclinical stage, is associated with changes in myocardial deformation and torsional mechanics that could be in part related to alterations in relaxation and contractility properties of subendocardial fibers.