Diet-induced hypercholesterolemia in rabbits was significantly associated with left ventricular systolic dysfunction, showing a strong inverse correlation between global longitudinal strain and serum LDL-C (r = -0.794).
Does an atherogenic diet impair left ventricular systolic function evaluated by speckle tracking echocardiography in a rabbit model?
In a rabbit model, hypercholesterolemia induced early left ventricular systolic dysfunction detectable by speckle-tracking echocardiography as reduced longitudinal and circumferential strain, despite preserved ejection fraction.
Effect estimate: r = -0.794
p-value: p=<0.001
BACKGROUND: Although hypercholesterolemia is a major risk factor for coronary artery disease (CAD), only limited data are available regarding its direct effect on myocardial function apart from CAD. The aim of this study was to evaluate LV systolic function using speckle-tracking echocardiography and investigate the relationship between hypercholesterolemia and myocardial function. METHODS: Twenty-eight rabbits were randomly divided into three groups: 8 were fed normal chow for 3 months (group 1) and the remaining 20 were fed an atherogenic diet for 2 (group 2) or 3 months (group 3). Global systolic radial, circumferential and longitudinal peak strain were calculated. Serum total cholesterol (TC), low density lipoprotein cholesterol (LDL-C) and myocardial cholesterol levels were measured. RESULTS: Global systolic longitudinal strain were both decreased in the group 2 and 3 (P < 0.001), whereas radial strain were increased (P < 0.001) compared with group 1. Global circumferential strain in the group 3 was significantly reduced (P < 0.001). Serum and myocardial cholesterol concentration markedly increased in the group 2 and group 3 (P < 0.001). There was a significant inverse correlation between longitudinal strain and serum TC, LDL-C as well as myocardial cholesterol levels (r = - 0.723, r = - 0.794, r = - 0.700, P both < 0.001). A significant negative correlation was also noted between circumferential strain and serum TC, LDL-C as well as myocardial cholesterol levels (r = - 0.518, P = 0.007; r = - 0.691, P < 0.001; r = - 0.659, P < 0.001). A significant positive correlation was found between radial strain and serum TC, LDL-C as well as myocardial cholesterol levels (r = 0.432, P = 0.028; r = 0.602, P = 0.001; r = 0.469, P = 0.016). CONCLUSION: Although LV morphology and ejection fractions were not different among the three groups, elevated concentration of cholesterol, especially in serum LDL-C, was significantly associated with LV systolic dysfunction. The findings also indicate that reductions in longitudinal was the first appeared, followed by circumferential, and was compensated for by increasing radial strain.
Liu et al. (Sat,) conducted a other in Hypercholesterolemia (n=28). Atherogenic diet vs. Normal chow was evaluated on Correlation between global systolic longitudinal strain and serum LDL-C (r = -0.794, p=<0.001). Diet-induced hypercholesterolemia in rabbits was significantly associated with left ventricular systolic dysfunction, showing a strong inverse correlation between global longitudinal strain and serum LDL-C (r = -0.794).