Obesity and left ventricular diastolic dysfunction.

To assess the influence of obesity on left ventricular function, 20 obese women (mean body mass index (BMI) 33.8 +/- 3.1 kg/m2 and mean age 31.1 +/- 2.4 years) without evidence of heart disease were evaluated by echocardiography. Obese subjects had greater left ventricular mass index (103 +/- 22 g/m2, 76 +/- 18 g/m2; P < 0.0001) and augmented fractional shortening (39 +/- 2.6%, 36 +/- 0.1%; P < 0.0001) than normals. Isovolumic relaxation time was prolonged in the obese group (92 +/- 11 ms) as compared with the control group (76 +/- 11 ms; P < 0.0001). The ratio of peak early and atrial filling velocities was significantly lower (1.2 +/- 0.4, 1.9 +/- 0.6; P < 0.0001) and atrial contribution was higher (39 +/- 9, 25 +/- 5; P < 0.0001) in obese subjects than in normals. Shortened deceleration time was measured in obese subjects (142 +/- 30, 179 +/- 20 ms; P < 0.0001). In conclusion, obesity causes relaxation and early filling abnormalities and diastolic filling is compensated by augmented atrial contribution. Diastolic dysfunction is an early indicator of cardiac involvement in obesity.