Left ventricular filling pattern in uncomplicated obesity.

ABSTRACT

To determine if uncomplicated obesity is associated with systolic dysfunction or impairment of left ventricular (LV) filling, 40 normotensive, white, asymptomatic, obese subjects (16 men and 24 women, mean +/- SD age 35 +/- 13 years; body mass index 36 +/- 6 kg/m2) and 40 normotensive, normal-weight, white volunteers matched for age and sex distribution, were studied by Doppler echocardiography. Endocardial and midwall shortening did not show differences between groups (obese = 33 +/- 4% and 17 +/- 2%; normal weight = 33 +/- 3% and 18 +/- 2%, respectively). LV mass index was higher in obese than in normal-weight subjects (p <0.0001). Obese persons had prolonged isovolumic relaxation time (p <0.0001), lower transmitral peak early diastolic filling wave (E) velocity (p <0.02), higher E velocity deceleration time (p <0.002) and lower E/atrial diastolic filling wave (A) flow velocity ratio (p <0.01) than did normal-weight subjects, even after controlling for age and blood pressure. Between-group differences in E and E velocity deceleration time disappeared when controlling for LV mass index, whereas prolonged isovolumic relaxation time in obesity was independent of LV mass, chamber dimension, and end-systolic stress. LV filling variables were not statistically related to endocardial or midwall shortening, both as absolute value or as a percentage of that predicted from wall stress. We conclude that uncomplicated obesity is associated with primary impairment of LV isovolumic relaxation; abnormalities of early passive filling flow in obesity are associated with increased LV mass.