Hypercholesterolemia and myocardial function evaluated via tissue doppler imaging.
OBJECTIVE
To establish a link between hypercholesterolemia and myocardial dysfunction.


BACKGROUND
Heart failure is a complex disease involving changes in systolic and diastolic function. Newer echocardiographic imaging modalities may be able to detect discreet changes in myocardial function associated with hypercholesterolemia. Therefore we sought to establish a link between hypercholesterolemia and myocardial dysfunction with tissue Doppler imaging (TDI).


METHODS
Twenty-seven rabbits were studied: 7 were fed normal chow (group 1) and 20 a high cholesterol diet (10 with ezetimibe, 1 mg/kg/day; group 2 and 10 without, group 3). Echocardiographic images were obtained under general anesthesia. Serum cholesterol levels were obtained at baseline, 3 and 6 months and myocardial cholesterol levels measured following euthanasia.


RESULTS
Doppler measurements, including E/A, E'/A' and S' were significantly lower in group 3 compared to both groups 1 and 2 but no significant differences were noted in chamber sizes or ejection fraction among the groups. Average serum cholesterol was higher in group 3 compared to groups 1 and 2 respectively (495 +/- 305 mg/dl vs. 114 +/- 95 mg/dl and 87 +/- 37 mg/dl; p < 0.01). Myocardial cholesterol content was also higher in group 3 compared to group 2 (0.10 +/- 0.04 vs. 0.06 mg/dl +/- 0.02; p = 0.05). There was significant correlation between S', E'/A', E/E' and serum cholesterol (r2 = 0.17 p = 0.04, r2 = 0.37 p = 0.001 and r2 = 0.24 p = 0.01).


CONCLUSIONS
Cholesterol load in the serum and myocardium was significantly associated with decreased systolic and diastolic function by TDI. Moreover, lipid lowering was protective.
Rubinstein
Jack
J
Department of Internal Medicine, Division of Cardiovascular Diseases, University of Cincinnati, Cincinnati, OH 45219, USA. rubinsjk@ucmail.uc.edu
Pelosi
Augusta
A
Vedre
Ameeth
A
Kotaru
Pavan
P
Abela
George S
GS
D000818:Animals; D002784:Cholesterol / Q000097:blood / Q000378:metabolism; D015150:Echocardiography, Doppler; D006937:Hypercholesterolemia / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology*; D008297:Male; D009206:Myocardium / Q000378:metabolism / Q000473:pathology; D011817:Rabbits; D016277:Ventricular Function, Left
D002784:Cholesterol