Comparison of epicardial and pericardial fat thickness assessed by echocardiography in African American and non-Hispanic White men: a pilot study.

OBJECTIVES: Compared to non-Hispanic Whites, African American men have less intra-abdominal visceral adipose tissue (VAT) relative to total fat mass despite having a higher risk of obesity-related diseases. This study explores whether this racial pattern of VAT distribution extends to the intrathoracic VAT.
METHODS: We used two-dimensional transthoracic echocardiography to measure pericardial and maximum and minimum epicardial fat thickness anterior to the right ventricle in 50 African American and 106 non-Hispanic White men, aged 40-75 years, consecutively referred for echocardiography for standard clinical indications. Age, coronary risk factors, height, and weight were recorded, and body mass index (BMI) was calculated. The two groups were compared with respect to pericardial and maximum, minimum, and average epicardial fat thicknesses.
RESULTS: Among non-Hispanic Whites, pericardial and minimum epicardial fat measured at the mid-rightventricular wall were higher by 37% and 69%, respectively, than among African Americans (5.2+/-3.1 mm vs 3.8+/-3.1 mm, P<.011; 2.2+/-1.6 mm vs 1.3+/-1.2 mm, P<.001). Maximum epicardial fat along the distal right ventricular wall was 19% greater in non-Hispanic Whites, but this difference was not statistically significant (4.3+/-2.6 mm vs 3.6+/-2.0 mm, P=.133). The average epicardial fat measured at two sites was 26% greater in non-Hispanic Whites (2.9+/-2.0 mm vs 2.3+/-1.3 mm, P=.019).
CONCLUSIONS: Among men referred for echocardiography, non-Hispanic Whites have more epicardial and pericardial fat than do African Americans. Echocardiography may be a useful research tool for investigating VAT distribution and its relationship to cardiovascular risk.